pake caranya biar ngerti. Hatur Nuhun:)

No.22
∠Δ  = 180°
Maka =
3x + 4x - 6 + 39° = 180°
7x + 33 = 180°
7x = 180 - 33
7x = 147
x  = 147 ÷ 7
x = 21

∠ABC = 4x - 6
           = 4(21) - 6
           = 84 - 6
           = 78°
Jadi Besar ∠ABC  = 78° (C)

No.23
∠QOR + ∠POR = 180°  (Berpelurus)
4x + 2x = 180°
6x = 180°
x = 180 ÷ 6
   = 30°

∠QOR = 2x
            = 2(30)
            = 60°
Jadi Besar ∠QOR = 60°(C)

No.24
∠BCD + ∠BCA = 180°          (Berpelurus)
108° + a = 180°
a = 180 - 108
   = 72°
∠Δ = 180°
∠BAC + ∠ABC + ∠BCA = 180°
x + 36 + 72 = 180°
x = 180 - 108
   = 72°
Jadi Besar ∠BAC = 72°(C)

No.25
∠Δ = 180°
Δ Sama Kaki = 2 sudut sama besar
∠PRQ + ∠PQR + ∠QPR = 180°
55° + x + x = 180°
2x = 180 - 55
2x = 125°
x = 125 ÷ 2
   = 62,5
∠TQR + ∠PQR = 180°                 (Berpelurus)
a + 62,5 = 180°
a = 180 - 62,5
   = 117,5
Jadi Besar ∠TQR = 117,5°(B)