Jawaban:

4.

a. Jumlah sudut segitiga adalah 180°

Jadi

60 + 2x + 3x = 180

5x = 180 - 60

5x = 120

x = 120/5 = 24°

b.

sudut P = 3x = 3(24) = 72°

sudut Q = 2x = 2(24) = 48°

sudut R = 60°

5.

a.

Keliling = 12+16+20 = 48 cm

Luas = 1/2 a x t = 1/2 x 16 x 12 = 96 cm2

b.

DB = √15^2 - 12^2

DB = √225 - 145

DB = √81 = 9 cm

Luas = 1/2 x alas x t

Luas = 1/2 x (16+9) x 12 = 1/2 x 25 x 12 = 150 cm2

AC = √25^2 - 15^2

AC = √625 - 225

AC = √400 = 20 cm

keliling = AB + BC + CA = 25+15+20 = 60 cm

c.

Luas = 1/2 x a x t = 1/2 x 19 + 12 = 114 cm2

DF = √5^2 + 12^2

DF = √25 + 144

DF = √169 = 13 cm

Keliling = DE + EF + DF = 14 + 21 + 13 = 48 cm

Penjelasan dengan langkah-langkah:

semoga membantu broooo