Higher January 2019 Paper 2R Q6
6
Diagram NOT accurately drawn
Pentagon \(ABCDE\) is drawn inside the regular octagon \(ABFGHIJK\).
The pentagon has exactly one line of symmetry.
Work out the value of \(x\).
(4)
| Scheme | Marks |
|---|---|
360 ÷ 8 (= 45 ) or 180 – (360 ÷ 8) (= 135) or \(\dfrac{6 \times 180}{8}\) (= 135) oe | M1 |
e.g. \(\dfrac{540 - 112 - 112 - 84}{2}\) (=116) or \(\dfrac{540 - 308}{2}\) (= 116) or \(\dfrac{232}{2}\) (= 116) | M1 |
| e.g. ‘135’ – ‘116’ or 180 – ‘116’ – ‘45’ | M1 |
| 19 | A1 |
| (4) | |
| (4 marks) |
Notes
M1: Correct method to find the interior or exterior angle of octagon
M1: Correct method to find a missing angle from pentagon
M1: Complete method