Construction: Draw a line || to PQ or RS through M
TZ || PQ
⇒ 135° + ∠1 = 180°
⇒ ∠1 = 180° – 135° = 45° …(i)
(Sum of interior angles on the same side of a transversal is 180°)
Also RS || TZ …(ii)
⇒ ∠2 = 40° (alternate interior angle)
Adding (i) and (ii), we get
∠1 + ∠2 = 45° + 40°
= 85°
