4400 Higher June 2005 Paper 4 Q3
3 In the diagram, \(PQR\) and \(PST\) are straight lines.
\(QS\) and \(RT\) are parallel lines.
Angle \(QRT = 70^\circ\).
Angle \(QST = 120^\circ\).
Diagram NOT accurately drawn
(a) Work out the value of \(x\). (3)
(b) Give a reason for each step in your working. (2)
| Scheme | Marks |
|---|---|
| 50° | B3 |
| (3) |
Notes
If B3 not gained: \(PQS = 70^\circ\) / \(\angle PTR = 60^\circ\) / ext \(\angle PTR = 120^\circ\) : B2
If B2 not gained: \(\angle PST = 60^\circ\) : B1
| Scheme | Marks |
|---|---|
| ∠s on a straight line = 180° or ∠ sum of triangle = 180° or ext ∠ of Δ = sum of int opp ∠s AND | B1 |
| Corresponding ∠s or alternate ∠s or allied or supp or included or interior or co-interior ∠s | B1 |
| (2) | |
| (5 marks) |