4MA0 Higher January 2016 Paper 3R Q11

EdexcelHigherOld spec3 marksSimultaneous Equations

11 Solve the simultaneous equations

\[\begin{aligned} c + 5d &= -13 \\ 4c - 5d &= 48 \end{aligned}\]

Show clear algebraic working.

(3)

Mark scheme

Scheme	Marks
Eg \(5c = 35\) or \(25d = -100\) or \(4(-13 - 5d) - 5d = 48\) oe	M1
\(c = 7\)	A1
\(d = -4\)	A1
	(3)

Notes

M1: For eliminating either variable by using the correct operation or for a correct rearrangement of one equation followed by a substitution into the other equation.
Condone 1 arithmetic error.

A1: dep on M1