TOLONG KERJAIN 3 SOAL DI BAWAH INIMAU DI KUMPULKAN MALAM INI​

Nomor 1

180 = ∠A + ∠D

180 = (3x – 25) + (4x – 5)

180 = 7x – 30

210 = 7x

x = 210/7

x = 30°

∠A dan ∠D berdekatan, Maka:

∠A = ∠C

∠D = ∠B

Hence,

∠B = ∠D

∠B = 4x – 5

∠B = 4(30) – 5

∠B = 120 – 5

∠B = 115°

Nomor 2

a) L = alas x tinggi

L = 15 x 8

L = 120 cm²

K = 2 x alas + 2 x sisi miring

K = 2 x 15 + 2 x 10

K = 30 + 20

K = 50 cm

b) L = alas x tinggi

L = 15 x 12

L = 180 cm²

Mencari sisi miring

c² = 12² + 5²

c² = 144 + 25

c² = 169

c = √169 = 13 cm

K = 2 x alas + 2 x sisi miring

K = 2 x 15 + 2 x 13

K = 30 + 26

K = 56 cm

Nomor 3

L = alas x tinggi

36 = 8 x tinggi

tinggi = 36/8

tinggi = 4,5 cm