// Numbas version: exam_results_page_options {"name": "Quadratic Equations: The Quadratic Formula (Instructional)", "metadata": {"description": "
Identify co-efficients, then use quadratic formula to find roots.
\nAll set to be distinct and real. Some can be non-integer (0.5 steps)
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", "licence": "Creative Commons Attribution 4.0 International"}, "statement": "\n
\\( \\LARGE x= \\frac{-b \\pm \\sqrt{b^2 -4ac}}{2a} \\)
\n\n
to find the roots of the equation. (Note the plus-or-minus means there are two solutions, not just one.)
\nIt is also sometimes known as Shreedhara Acharya's formula, named after the 10th century Indian mathematician who first derived it.
", "advice": "We are asked to find the roots of various quadratic equations using the Quadratic Formula. To enable us to do this, we are first asked to identify the co-efficients \\( a \\), \\( b \\) and \\( c \\) each time.
\n\na)
\n\\( \\simplify{ {a1}x^2 + {b1}x + {c1} } =0 \\)
\nThe co-efficients of this equation can simply be read from the equation, taking care to take account of positive and negative values:
\n\\( a = \\) \\( \\var{a1}\\) \\( b = \\) \\( \\var{b1}\\) and \\( c = \\) \\( \\var{c1}\\)
\nWe now write the equation substituting these values in the correct places and, again, being careful with any negative values:
\n\\( x= \\frac{-b \\pm \\sqrt{b^2 -4ac}}{2a} \\) becomes \\( x= \\frac{-(\\var{b1}) \\pm \\sqrt{(\\var{b1})^2 -4 \\times (\\var{a1}) \\times (\\var{c1})}}{2 \\times (\\var{a1})} \\)
\nSimplify this as much as possible (mainly the expression inside the square root and the denominator):
\n\\( x= \\frac{\\simplify{-{b1}} \\pm \\sqrt{\\simplify{{b1}^2 -4*{a1}*{c1}}}}{\\simplify{2{a1}}} \\)
\nNow, carry out this calculation twice, first using the plus (\\( + \\)) and then using the minus (\\( - \\)).
\nThis will give you the two roots: \\( x = \\var{x1} \\) and \\( x = \\var{x2} \\)
\n\n
\n
b)
\n\\( \\simplify{ {a2}x^2 + {b2}x + {c2} } =0 \\)
\nThe co-efficients of this equation can simply be read from the equation, taking care to take account of positive and negative values:
\n\\( a = \\) \\( \\var{a2}\\) \\( b = \\) \\( \\var{b2}\\) and \\( c = \\) \\( \\var{c2}\\)
\nWe now write the equation substituting these values in the correct places and, again, being careful with any negative values:
\n\\( x= \\frac{-b \\pm \\sqrt{b^2 -4ac}}{2a} \\) becomes \\( x= \\frac{-(\\var{b2}) \\pm \\sqrt{(\\var{b2})^2 -4 \\times (\\var{a2}) \\times (\\var{c2})}}{2 \\times (\\var{a2})} \\)
\nSimplify this as much as possible (mainly the expression inside the square root and the denominator):
\n\\( x= \\frac{\\simplify{-{b2}} \\pm \\sqrt{\\simplify{{b2}^2 -4*{a2}*{c2}}}}{\\simplify{2{a2}}} \\)
\nNow, carry out this calculation twice, first using the plus (\\( + \\)) and then using the minus (\\( - \\)).
\nThis will give you the two roots: \\( x = \\var{y1} \\) and \\( x = \\var{y2} \\)
\n\n
\n
c)
\n\\( \\simplify{ {a3}x^2 + {b3}x + {c3} } =0 \\)
\nThe co-efficients of this equation can simply be read from the equation, taking care to take account of positive and negative values:
\n\\( a = \\) \\( \\var{a3}\\) \\( b = \\) \\( \\var{b3}\\) and \\( c = \\) \\( \\var{c3}\\)
\nWe now write the equation substituting these values in the correct places and, again, being careful with any negative values:
\n\\( x= \\frac{-b \\pm \\sqrt{b^2 -4ac}}{2a} \\) becomes \\( x= \\frac{-(\\var{b3}) \\pm \\sqrt{(\\var{b3})^2 -4 \\times (\\var{a3}) \\times (\\var{c3})}}{2 \\times (\\var{a3})} \\)
\nSimplify this as much as possible (mainly the expression inside the square root and the denominator):
\n\\( x= \\frac{\\simplify{-{b3}} \\pm \\sqrt{\\simplify{{b3}^2 -4*{a3}*{c3}}}}{\\simplify{2{a3}}} \\)
\nNow, carry out this calculation twice, first using the plus (\\( + \\)) and then using the minus (\\( - \\)).
\nThis will give you the two roots: \\( x = \\var{z1} \\) and \\( x = \\var{z2} \\)
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\nThe co-efficients of this equation are:
\n\\( a = \\) [[0]] \\( b = \\) [[1]] and \\( c = \\) [[2]]
\n\n
Now use the formula to find the roots:
\n\\( x_1 = \\) [[3]]
\n\\( x_2 = \\) [[4]]
\n(If you are sure that your roots are correct but they are marked wrong, switch them around).
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\nThe co-efficients of this equation are:
\n\\( a = \\) [[0]] \\( b = \\) [[1]] and \\( c = \\) [[2]]
\n\n
Now use the formula to find the roots:
\n\\( x_1 = \\) [[3]]
\n\\( x_2 = \\) [[4]]
\n(If you are sure that your roots are correct but they are marked wrong, switch them around).
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\nThe co-efficients of this equation are:
\n\\( a = \\) [[0]] \\( b = \\) [[1]] and \\( c = \\) [[2]]
\n\n
Now use the formula to find the roots:
\n\\( x_1 = \\) [[3]]
\n\\( x_2 = \\) [[4]]
\n(If you are sure that your roots are correct but they are marked wrong, switch them around).
", "gaps": [{"type": "numberentry", "useCustomName": false, "customName": "", "marks": 1, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "minValue": "{a3}", "maxValue": "{a3}", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": 1, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "minValue": "{b3}", "maxValue": "{b3}", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": 1, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "minValue": "{c3}", "maxValue": "{c3}", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": 1, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "minValue": "{z1}", "maxValue": "{z1}", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": 1, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "minValue": "{z2}", "maxValue": "{z2}", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}], "sortAnswers": false}], "partsMode": "all", "maxMarks": 0, "objectives": [], "penalties": [], "objectiveVisibility": "always", "penaltyVisibility": "always"}, {"name": "Quadratic Equations: The Quadratic Formula 02", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "contributors": [{"name": "Michael Proudman", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/269/"}], "tags": [], "metadata": {"description": "Solve quadratic equations (non-simple case, two real, discrete roots) using the formula. Some, random, non integer roots.
", "licence": "Creative Commons Attribution 4.0 International"}, "statement": "\n
\\( \\LARGE x= \\frac{-b \\pm \\sqrt{b^2 -4ac}}{2a} \\)
\n\n
to find the roots of the equation. (Note the plus-or-minus means there are two solutions, not just one.)
\nIt is also sometimes known as Shreedhara Acharya's formula, named after the 10th century Indian mathematician who first derived it.
", "advice": "We are asked to find the roots of various quadratic equations using the Quadratic Formula. To enable us to do this, we are first asked to identify the co-efficients \\( a \\), \\( b \\) and \\( c \\) each time.
\n\na)
\n\\( \\simplify{ {a1}x^2 + {b1}x + {c1} } =0 \\)
\nThe co-efficients of this equation can simply be read from the equation, taking care to take account of positive and negative values:
\n\\( a = \\) \\( \\var{a1}\\) \\( b = \\) \\( \\var{b1}\\) and \\( c = \\) \\( \\var{c1}\\)
\nWe now write the equation substituting these values in the correct places and, again, being careful with any negative values:
\n\\( x= \\frac{-b \\pm \\sqrt{b^2 -4ac}}{2a} \\) becomes \\( x= \\frac{-(\\var{b1}) \\pm \\sqrt{(\\var{b1})^2 -4 \\times (\\var{a1}) \\times (\\var{c1})}}{2 \\times (\\var{a1})} \\)
\nSimplify this as much as possible (mainly the expression inside the square root and the denominator):
\n\\( x= \\frac{\\simplify{-{b1}} \\pm \\sqrt{\\simplify{{b1}^2 -4*{a1}*{c1}}}}{\\simplify{2{a1}}} \\)
\nNow, carry out this calculation twice, first using the plus (\\( + \\)) and then using the minus (\\( - \\)).
\nThis will give you the two roots: \\( x = \\var{x1} \\) and \\( x = \\var{x2} \\)
\n\n
\n
b)
\n\\( \\simplify{ {a2}x^2 + {b2}x + {c2} } =0 \\)
\nThe co-efficients of this equation can simply be read from the equation, taking care to take account of positive and negative values:
\n\\( a = \\) \\( \\var{a2}\\) \\( b = \\) \\( \\var{b2}\\) and \\( c = \\) \\( \\var{c2}\\)
\nWe now write the equation substituting these values in the correct places and, again, being careful with any negative values:
\n\\( x= \\frac{-b \\pm \\sqrt{b^2 -4ac}}{2a} \\) becomes \\( x= \\frac{-(\\var{b2}) \\pm \\sqrt{(\\var{b2})^2 -4 \\times (\\var{a2}) \\times (\\var{c2})}}{2 \\times (\\var{a2})} \\)
\nSimplify this as much as possible (mainly the expression inside the square root and the denominator):
\n\\( x= \\frac{\\simplify{-{b2}} \\pm \\sqrt{\\simplify{{b2}^2 -4*{a2}*{c2}}}}{\\simplify{2{a2}}} \\)
\nNow, carry out this calculation twice, first using the plus (\\( + \\)) and then using the minus (\\( - \\)).
\nThis will give you the two roots: \\( x = \\var{y1} \\) and \\( x = \\var{y2} \\)
\n\n
\n
c)
\n\\( \\simplify{ {a3}x^2 + {b3}x + {c3} } =0 \\)
\nThe co-efficients of this equation can simply be read from the equation, taking care to take account of positive and negative values:
\n\\( a = \\) \\( \\var{a3}\\) \\( b = \\) \\( \\var{b3}\\) and \\( c = \\) \\( \\var{c3}\\)
\nWe now write the equation substituting these values in the correct places and, again, being careful with any negative values:
\n\\( x= \\frac{-b \\pm \\sqrt{b^2 -4ac}}{2a} \\) becomes \\( x= \\frac{-(\\var{b3}) \\pm \\sqrt{(\\var{b3})^2 -4 \\times (\\var{a3}) \\times (\\var{c3})}}{2 \\times (\\var{a3})} \\)
\nSimplify this as much as possible (mainly the expression inside the square root and the denominator):
\n\\( x= \\frac{\\simplify{-{b3}} \\pm \\sqrt{\\simplify{{b3}^2 -4*{a3}*{c3}}}}{\\simplify{2{a3}}} \\)
\nNow, carry out this calculation twice, first using the plus (\\( + \\)) and then using the minus (\\( - \\)).
\nThis will give you the two roots: \\( x = \\var{z1} \\) and \\( x = \\var{z2} \\)
\n\n\n\n", "rulesets": {}, "builtin_constants": {"e": true, "pi,\u03c0": true, "i": true}, "constants": [], "variables": {"a1": {"name": "a1", "group": "Question A", "definition": "random(2..9)", "description": "", "templateType": "anything", "can_override": false}, "x1": {"name": "x1", "group": "Question A", "definition": "random(-9..9 #0.5 except 0 except 1 except {a1})", "description": "", "templateType": "anything", "can_override": false}, "x2": {"name": "x2", "group": "Question A", "definition": "random(-9..9 except 0 except 1 except {a1} except {x1})", "description": "", "templateType": "anything", "can_override": false}, "b1": {"name": "b1", "group": "Question A", "definition": "-{a1}*({x1}+{x2})", "description": "", "templateType": "anything", "can_override": false}, "c1": {"name": "c1", "group": "Question A", "definition": "{a1}*{x1}*{x2}", "description": "", "templateType": "anything", "can_override": false}, "a2": {"name": "a2", "group": "Question B", "definition": "random(2..9 except {a1})", "description": "", "templateType": "anything", "can_override": false}, "y1": {"name": "y1", "group": "Question B", "definition": "random(-9..9 #0.5 except 0 except 1 except {a2}) ", "description": "", "templateType": "anything", "can_override": false}, "y2": {"name": "y2", "group": "Question B", "definition": "random(-9..9 except 0 except 1 except {a2} except {y1})", "description": "", "templateType": "anything", "can_override": false}, "b2": {"name": "b2", "group": "Question B", "definition": "-{a2}*({y1}+{y2})", "description": "", "templateType": "anything", "can_override": false}, "c2": {"name": "c2", "group": "Question B", "definition": "{a2}*{y1}*{y2}", "description": "", "templateType": "anything", "can_override": false}, "a3": {"name": "a3", "group": "Question C", "definition": "random(2..9 except {a1} except {a2})", "description": "", "templateType": "anything", "can_override": false}, "z1": {"name": "z1", "group": "Question C", "definition": "random(-9..9 except 0 except 1 except {a3})", "description": "", "templateType": "anything", "can_override": false}, "z2": {"name": "z2", "group": "Question C", "definition": "random(-9..9 #0.5 except 0 except 1 except {a3} except {z1})", "description": "", "templateType": "anything", "can_override": false}, "b3": {"name": "b3", "group": "Question C", "definition": "-{a3}*({z1}+{z2})", "description": "", "templateType": "anything", "can_override": false}, "c3": {"name": "c3", "group": "Question C", "definition": "{a3}*{z1}*{z2}", "description": "", "templateType": "anything", "can_override": false}}, "variablesTest": {"condition": "", "maxRuns": 100}, "ungrouped_variables": [], "variable_groups": [{"name": "Question B", "variables": ["y1", "y2", "a2", "b2", "c2"]}, {"name": "Question C", "variables": ["z1", "z2", "a3", "b3", "c3"]}, {"name": "Question A", "variables": ["x1", "x2", "a1", "b1", "c1"]}], "functions": {}, "preamble": {"js": "", "css": ""}, "parts": [{"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "For the following equations, first identify the co-efficients, then use the formula to calculate the roots:
"}, {"type": "gapfill", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": false, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "\\( \\simplify{ {a1}x^2 + {b1}x + {c1} } =0 \\)
\nThe co-efficients of this equation are:
\n\\( a = \\) [[0]] \\( b = \\) [[1]] and \\( c = \\) [[2]]
\n\n
Now use the formula to find the roots:
\n\\( x_1 = \\) [[3]]
\n\\( x_2 = \\) [[4]]
\n(If you are sure that your roots are correct but they are marked wrong, switch them around).
", "gaps": [{"type": "numberentry", "useCustomName": false, "customName": "", "marks": 1, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "minValue": "{a1}", "maxValue": "{a1}", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": 1, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "minValue": "{b1}", "maxValue": "{b1}", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": 1, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "minValue": "{c1}", "maxValue": "{c1}", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": 1, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "minValue": "{x1}", "maxValue": "{x1}", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": 1, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "minValue": "{x2}", "maxValue": "{x2}", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}], "sortAnswers": false}, {"type": "gapfill", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": false, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "\\( \\simplify{ {a2}x^2 + {b2}x + {c2} } =0 \\)
\nThe co-efficients of this equation are:
\n\\( a = \\) [[0]] \\( b = \\) [[1]] and \\( c = \\) [[2]]
\n\n
Now use the formula to find the roots:
\n\\( x_1 = \\) [[3]]
\n\\( x_2 = \\) [[4]]
\n(If you are sure that your roots are correct but they are marked wrong, switch them around).
", "gaps": [{"type": "numberentry", "useCustomName": false, "customName": "", "marks": 1, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "minValue": "{a2}", "maxValue": "{a2}", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": 1, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "minValue": "{b2}", "maxValue": "{b2}", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": 1, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "minValue": "{c2}", "maxValue": "{c2}", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": 1, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "minValue": "{y1}", "maxValue": "{y1}", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": 1, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "minValue": "{y2}", "maxValue": "{y2}", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}], "sortAnswers": false}, {"type": "gapfill", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": false, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "\\( \\simplify{ {a3}x^2 + {b3}x + {c3} } =0 \\)
\nThe co-efficients of this equation are:
\n\\( a = \\) [[0]] \\( b = \\) [[1]] and \\( c = \\) [[2]]
\n\n
Now use the formula to find the roots:
\n\\( x_1 = \\) [[3]]
\n\\( x_2 = \\) [[4]]
\n(If you are sure that your roots are correct but they are marked wrong, switch them around).
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