1MA0 Foundation June 2014 Paper 1 Q16
*16
Diagram NOT accurately drawn
\(ABC\) is a straight line.
\(AB = BD\)
Angle \(BAD = 25^\circ\)
Angle \(BCD = 70^\circ\)
Work out the size of the angle marked \(x\).
Give reasons for your answer. (4)
| Working | Answer | Mark | Notes |
|---|---|---|---|
| base angles of isosceles triangle are equal and angles on a straight line add up to 180° and angles in a triangle add up to 180° OR base angles of isosceles triangle are equal and angles in a triangle add up to 180° OR base angles of isosceles triangle are equal and exterior angle of a triangle is equal to the sum of the interior opposite angles | 60° with reasons | 4 | B1 for angle \(ADB = 25\) can be shown on the diagram M1 for a complete method to find \(x\) C2 (dep 2 previous marks) for 60 with full reasoning seen (C1 (dep 1 previous mark) for one reason) QWC: Reasons must be appropriate to the method shown. |