OCR MEI C1 2015 June — Question 5 4 marks

Exam BoardOCR MEI
ModuleC1 (Core Mathematics 1)
Year2015
SessionJune
Marks4
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicStraight Lines & Coordinate Geometry
TypeIntersection of two lines
DifficultyEasy -1.2 This is a straightforward two-line intersection problem requiring only substitution of one equation into the other and basic algebraic manipulation. It's simpler than average A-level questions as it involves no problem-solving insight, just routine application of a standard technique with minimal steps.
Spec1.02c Simultaneous equations: two variables by elimination and substitution

5 Find the coordinates of the point of intersection of the lines \(y = 5 x - 2\) and \(x + 3 y = 8\).

Question 5:
AnswerMarks Guidance
AnswerMarks Guidance
\(x + 3(5x-2) = 8\) or \(y = 5(8-3y) - 2\)M1 For subst to eliminate one variable; condone one error; or multn or divn of one or both eqns to get a pair of coeffts the same, condoning one error
\(16x = 14\) or \(16y = 38\)M1 For collecting terms and simplifying; condoning one error ft; appropriate addn or subtn to eliminate a variable, condoning an error in one term; if subtracting, condone eg \(y\) instead of 0 if no other errors
\((7/8, 19/8)\) oeA2 or \(x = 14/16\), \(y = 38/16\) oe isw; allow A1 for each coordinate
## Question 5:
| Answer | Marks | Guidance |
|--------|-------|----------|
| $x + 3(5x-2) = 8$ or $y = 5(8-3y) - 2$ | M1 | For subst to eliminate one variable; condone one error; or multn or divn of one or both eqns to get a pair of coeffts the same, condoning one error |
| $16x = 14$ or $16y = 38$ | M1 | For collecting terms and simplifying; condoning one error ft; appropriate addn or subtn to eliminate a variable, condoning an error in one term; if subtracting, condone eg $y$ instead of 0 if no other errors |
| $(7/8, 19/8)$ oe | A2 | or $x = 14/16$, $y = 38/16$ oe isw; allow A1 for each coordinate |
5 Find the coordinates of the point of intersection of the lines $y = 5 x - 2$ and $x + 3 y = 8$.

\hfill \mbox{\textit{OCR MEI C1 2015 Q5 [4]}}