Foundation June 2018 Paper 2R Q24
24
Diagram NOT accurately drawn
The diagram shows a regular pentagon, \(ABCDE\), a regular octagon, \(ABFGHIJK\), and an isosceles triangle, \(BCF\).
Work out the size of angle \(x\).
(4)
| Scheme | Marks |
|---|---|
| Interior angle of pentagon (180 × 3) ÷ 5 (= 108) oe | M1 |
| Interior angle of octagon (180 × 6) ÷ 8 (= 135) oe | M1 |
| (\(CBF\) =) 360 – (“108” + “135”) (= 117) | M1 |
| 31.5 | A1 |
| (4) | |
| (4 marks) |
Notes
M1: or exterior angle of pentagon = \(\dfrac{360}{5}\) (= 72)
M1: or exterior angle of octagon = \(\dfrac{360}{8}\) (= 45)
M1: (\(CBF\) =) “72” + “45” (= 117)