PSLE Julie has a triangular piece of paper JKL with KJ = KL, ∠JKL = 76° and ∠LMM = 71°. JML and KML are straight lines. She folded it along the line MN as shown.
- Find ∠p.
- Find ∠q.
(a)
Length of JK = Length of KL
Triangle JKL is an isosceles triangle.
∠KLJ
= (180° - 76°) ÷ 2
= 104° ÷ 2
= 52° (Isosceles triangle)
∠p
= 180° - 71° - 52°
= 57° (Angles sum of triangle)
(b)
∠KJL = ∠KLJ = 52°
∠r
= 180° - 71° - 71°
= 38° (Angles on a straight line)
∠q
= 180° - 52° - 38°
= 90° (Angles sum of triangle)
Answer(s): (a) 57°; (b) 90°