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Find the equation of a straight line which has a given slope or gradient $m$ and passes through the given point $(a,b)$.

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There is a video in Show steps which goes through a similar example.

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$y=\\;\\phantom{{}}$[[0]]

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The equation of the line is of the form $y=mx+c$.

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You are given the slope or gradient $m$ and you can calculate the constant term $c$ by noting that $y=\\var{b}$ when $x=\\var{a}$.

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The following video goes through a similar example.

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\n\t\t\t\t\t \n\t\t\t\t\t \n\t\t\t\t\t \n\t\t\t\t\t \n\t\t\t\t\t", "variableReplacements": [], "unitTests": [], "marks": 0, "extendBaseMarkingAlgorithm": true, "showFeedbackIcon": true, "scripts": {}}], "variableReplacements": [], "unitTests": [], "marks": 0, "extendBaseMarkingAlgorithm": true, "showFeedbackIcon": true, "scripts": {}, "gaps": [{"customName": "", "variableReplacementStrategy": "originalfirst", "vsetRangePoints": 5, "checkVariableNames": false, "answer": "({b-d}/{a-c})x+{b*c-a*d}/{c-a}", "vsetRange": [0, 1], "unitTests": [], "extendBaseMarkingAlgorithm": true, "showFeedbackIcon": true, "scripts": {}, "type": "jme", "useCustomName": false, "customMarkingAlgorithm": "", "showCorrectAnswer": true, "notallowed": {"partialCredit": 0, "message": "

Input all numbers as fractions or integers as appropriate and not as decimals.

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Find the equation of the straight line which:

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Input your answer in the form $mx+c$ for suitable values of $m$ and $c$.

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Input $m$ and $c$ as fractions or integers as appropriate and not as decimals.

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Click on \"Show steps\" if you need help, you will lose 1 mark if you do so.

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Note that there is also a video in Show steps which goes through a similar example.

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The equation of the line is of the form $y=mx+c$.

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You are given the slope or gradient $\\displaystyle m= \\simplify{{b-d}/{a-c}}$ and we can calculate the constant term $c$ by noting that $y=\\var{b}$ when $x=\\var{a}$.

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Using this we get:
\\[ \\begin{eqnarray} \\var{b}&=&\\simplify[std]{({b-d}/{a-c}){a}+c} \\Rightarrow\\\\ c&=&\\simplify[std]{{b}-({b-d}/{a-c}){a}={(b*c-a*d)}/{(c-a)}} \\end{eqnarray} \\]

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Hence the equation of the line is
\\[y = \\simplify[std]{({b-d}/{a-c})x+{b*c-a*d}/{c-a}}\\]

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