// Numbas version: exam_results_page_options {"name": "Luis's copy of Solving equations", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"ungrouped_variables": ["a", "c", "b", "d", "s2", "s1", "b1", "t", "an2", "an1"], "metadata": {"notes": "
5/08/2012:
\nAdded tags.
\nAdded description.
\nChecked calculation.OK.
\nImproved display in content areas.
", "description": "Solve for $x$: $\\displaystyle \\frac{a} {bx+c} + d= s$
", "licence": "Creative Commons Attribution 4.0 International"}, "advice": "Rearrange the equation by adding {-c} to both sides to get:
\\[\\simplify{{t} / ({a} * x + {b}) = {d} + { -c} = {d -c}}\\]
This gives \\[\\simplify{({a} * x + {b}) / {t} = 1 / {d -c}}\\] (this is because if $\\displaystyle \\frac{a}{b}=c$ then $\\displaystyle \\frac{b}{a}=\\frac{1}{c}$ on turning the fraction round the other way)
and so \\[\\simplify{({a} * x + {b}) = {t} / {d -c}}\\] on multiplying both sides by {t}.
Hence \\[\\simplify{{a} * x = {t} / {d -c} -{b} = ({a * an1} / {an2})}\\]
and so \\[\\simplify{x={an1}/{an2}}\\] is the solution on dividing both sides by {a}.
Input as a fraction or an integer, not as a decimal.
", "showStrings": false}, "answersimplification": "std", "checkingaccuracy": 0.0001}], "type": "gapfill", "prompt": "\\[\\simplify{{t} / ({a} * x + {b}) + {c} = {d}}\\]
\n$x=\\;$ [[0]]
\nIf you want help in solving the equation, click on Show steps. If you do so then you will lose 1 mark.
\nInput all numbers as fractions or integers and not as decimals.
", "steps": [{"scripts": {}, "marks": 0, "prompt": "Rearrange the equation by adding {-c} to both sides to get:
\\[\\simplify[std]{{t} / ({a} * x + {b}) = {d} + { -c} = {d -c}}\\]
This gives \\[\\simplify{({a} * x + {b}) / {t} = 1 / {d -c}}\\] (this is because if $\\displaystyle \\frac{a}{b}=c$ then $\\displaystyle \\frac{b}{a}=\\frac{1}{c}$ on turning the fraction round the other way)
\nand so \\[\\simplify{({a} * x + {b}) = {t} / {d -c}}\\] on multiplying both sides by {t}.
\nSolve this equation for $x$.
", "type": "information", "showCorrectAnswer": true}]}], "functions": {}, "variablesTest": {"maxRuns": 100, "condition": ""}, "question_groups": [{"questions": [], "pickingStrategy": "all-ordered", "pickQuestions": 0, "name": ""}], "statement": "Solve the following equation for $x$.
\nInput your answer as a fraction or an integer as appropriate and not as a decimal.
", "rulesets": {"std": ["all", "!collectNumbers", "fractionNumbers", "!noLeadingMinus"]}, "tags": ["algebra", "algebraic fractions", "algebraic manipulation", "changing the subject of an equation", "checked2015", "MAS1601", "mas1601", "rearranging equations", "solving", "solving equations", "Solving equations", "subject of an equation"], "variables": {"an1": {"description": "", "group": "Ungrouped variables", "name": "an1", "definition": "t-b*d+b*c", "templateType": "anything"}, "b1": {"description": "", "group": "Ungrouped variables", "name": "b1", "definition": "s1*random(1..10)", "templateType": "anything"}, "d": {"description": "", "group": "Ungrouped variables", "name": "d", "definition": "abs(c)+random(2..9)", "templateType": "anything"}, "s2": {"description": "", "group": "Ungrouped variables", "name": "s2", "definition": "random(1,-1)", "templateType": "anything"}, "a": {"description": "", "group": "Ungrouped variables", "name": "a", "definition": "random(2..9)", "templateType": "anything"}, "b": {"description": "", "group": "Ungrouped variables", "name": "b", "definition": "if(a=abs(b1),abs(b1)+2,b1)", "templateType": "anything"}, "an2": {"description": "", "group": "Ungrouped variables", "name": "an2", "definition": "a*(d-c)", "templateType": "anything"}, "c": {"description": "", "group": "Ungrouped variables", "name": "c", "definition": "s2*random(1..9)", "templateType": "anything"}, "s1": {"description": "", "group": "Ungrouped variables", "name": "s1", "definition": "random(-1,1)", "templateType": "anything"}, "t": {"description": "", "group": "Ungrouped variables", "name": "t", "definition": "random(2..8)", "templateType": "anything"}}, "name": "Luis's copy of Solving equations", "contributors": [{"name": "Newcastle University Mathematics and Statistics", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/697/"}, {"name": "Luis Hernandez", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/2870/"}]}]}], "contributors": [{"name": "Newcastle University Mathematics and Statistics", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/697/"}, {"name": "Luis Hernandez", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/2870/"}]}