In the figure, MN is a straight line. ∠LPM = 90°, ∠QPR is equal to ∠RPN but 21° more than ∠LPQ.
- What line is perpendicular to MN?
- Find ∠QPR.
(a)
Line LP or PL is perpendicular to MN
(b)
∠QPR = ∠RPN = 1 u
∠LPQ = 1 u - 21°
1 u + 1 u + 1 u - 21° = 90° (Right angle)
3 u = 90° + 21° = 111°
1 u = 111° ÷ 3 = 37°
Answer(s): (a) LP or PL; (b) 37°