Higher June 2023 Paper 5 Q2

OCRHigherCurrent spec5 marksAngles (Including Parallel Lines)

2 The diagram shows two straight lines crossing a pair of parallel lines.

Two parallel lines crossed by two straight lines that meet above them at angle b°; angle 125° is marked on the upper parallel line, angle a° on the lower parallel line, and angle 75° on the lower parallel line at the right-hand line

Not to scale

(a) Write down the value of \(a\).
Give a reason for your answer. [2]
(b) Work out the value of \(b\). [3]