4MA0 Foundation January 2014 Paper 2 Q11
11
Diagram NOT accurately drawn
The diagram shows an equilateral triangle \(ABC\) and an isosceles triangle \(BCD\).
\(AB = AC = BC = CD\).
Angle \(ACD = 52^\circ\)
Angle \(ACB = x^\circ\)
(i) Find the value of \(x\).
Angle \(ABD = y^\circ\)
(ii) Work out the value of \(y\).
(4)
| Scheme | Marks |
|---|---|
| (i) Answer: 60 | B1 |
| (ii) \((BCD =)\) “60” + 52 (= 112°) \((CBD\) or \(BDC =)\) (180 − “112”) ÷ 2 (= 34°) | M1ft |
| \((DBC =)\) “60” − “34” | M1ft |
| 26 | A1 |
| (4) | |
| (Total 4 marks) |
Notes
B1: Look on diagram if no answer on answer line.
M1ft: Their ft from angle x. Can be marked on diagram.
M1ft: (Dep) Dependent on previous M1
Their x − “CBD”
A1: cao
The printed working writes \((DBC =)\) for the last line; the angle found is \(ABD = y\).