cari nilai x + y= dan cara pengiraannya

< STR = 1/2 × (180° - 110°)
< STR = 1/2 × 70
< STR = 35°
< PTR = 90°
x = 180° - (< PTR + < STR)
x = 180° - (90° + 35°)
x = 180° - 125°
x = 55°

< RQV = < TRQ
y = 80°

nilai x + y = 55° + 80° = 135°

Jadi nilai x + y adalah 135°