Higher November 2017 Paper 1 Q24
24 Here is a cyclic quadrilateral.

Not drawn accurately
\(x : y \;=\; 5 : 7\)
Work out the size of angle \(w\). [4 marks]
| Answer | Mark | Comments |
|---|---|---|
| Alternative method 1 | ||
| \(180 \div (5 + 7)\) or \(180 \div 12\) or 15 | M1 | oe |
| \(5 \times\) their 15 or \(180 - 7 \times\) their 15 or 75 | M1dep | oe |
| \(180 -\) their \(75 - 20\) or \(180 - 95\) | M1dep | oe |
| 85 | A1 | |
| Alternative method 2 | ||
| \(x + \dfrac{7x}{5} = 180\) or \(\dfrac{5y}{7} + y = 180\) or \(y = 105\) | M1 | oe correct elimination of a variable from equations \(x + y = 180\) and \(7x = 5y\) |
| (\(x =\)) \(180 \times \dfrac{5}{12}\) or (\(x =\)) 75 | M1dep | oe |
| \(180 -\) their \(75 - 20\) or \(180 - 95\) | M1dep | oe |
| 85 | A1 | |