In the figure, not drawn to scale. FGHJ is a square. HJK is an equilateral triangle and FH is a straight line. Find
- Four-fifths of ∠FLK
- Five times of ∠KHL
(a)
∠JFH = 45° (Right angle)
∠LJH = 60° (Equilateral triangle)
∠FJL
= 90° - ∠LJH
= 90° - 60°
= 30°
∠FLK
= 30° + 45° (Exterior angle of a triangle)
= 75°
Four-fifths of ∠FLK
=
45 x 75°
= 60°
(b)
∠KLH
= 180° - ∠FLK
= 180° - 75°
= 105° (Angles on a straight line)
∠KHL
= 180° - 60° - 105°
= 15° (Angles sum of triangle)
Five times of ∠KHL
= 5 x 15°
= 75°
Answer(s): (a) 60°; (b) 75°
