1MA0 Higher November 2015 Paper 1 Q6

Diagram NOT accurately drawn

\(ABCD\) and \(EFG\) are parallel lines.
\(BC = CF\)
Angle \(BFE = 70^\circ\)

Work out the size of the angle marked \(x\).
Give reasons for each stage of your working. (4)

Mark scheme

Answer	Mark	Notes
\(40^\circ\)	4	M1 for angle \(FBC = 70\) or \(CFG = x\) or \(ABF = 110\) may be seen in diagram M1 for angle \(CBF = BFC = 70\) or \(90 - \tfrac{1}{2}x\) A1 for 40 supported by working C1 (dep on M2) for all reasons and linked to appropriate working, e.g. Alternate angles are equal; Allied angles / Co-interior angles add up to \(180^\circ\); Base angles of an isosceles triangle are equal; angles in a triangle add to \(180^\circ\), angles on a straight line equals \(180^\circ\)