nomor 5 soal matematika kls 8

m ∠ BAD = x + 20°
m ∠ BCD = 3x

∠BOD minor = 2 (x + 20) = 2x + 40
∠BOD mayor = 2 (3x) = 6x

∠BOD minor + ∠BOD = 360
2x + 40 + 6x = 360
2x + 6x = 360 - 40
8x = 320
x = 320/8
x = 40

∠BOD minor = 2x + 40
= 2(40) + 40
= 120°

∠BOD mayor = 6x
= 6(40)
= 240°