Higher November 2017 Paper 2 Q12
12
\(RS\) and \(ST\) are 2 sides of a regular 12-sided polygon.
\(RT\) is a diagonal of the polygon.
Work out the size of angle \(STR\).
You must show your working. (3)
| Answer | Mark | Notes |
|---|---|---|
| 15 | P1 | for a process to find the interior or exterior angle of a regular 12 sided polygon e.g. \(\dfrac{10 \times 180}{12}\ (= 150)\) or \(\dfrac{360}{12}\ (= 30)\), must be no contradictions |
| P1 | for process to find angle \(STR\), eg \(\dfrac{180 - \text{``}150\text{''}}{2}\) or \(\dfrac{\text{``}30\text{''}}{2}\) | |
| A1 | cao |