Jawaban:

1) garis yg sejajar = AB, DC, EF, HG

garis yg saling tegak lurus = AE, BF, HD, GC

2) pada gambar

3) <g1 = <g3 = <h7 = <h5 = 95⁰

<g2 = <g4 = <h6 = <h8 = 180⁰ - 95⁰ = 85⁰

4) gambar 1

8x + 5⁰ = 135⁰

8x = 135⁰ - 5⁰

8x = 130⁰

x = 130⁰ : 8

x = 16,25⁰

gambar 2

4x = 80⁰

x = 80⁰ : 4

x = 20⁰

(4z - 20)⁰ + 80⁰ = 180⁰

4z = 180⁰ + 20⁰ - 80⁰

4z = 120⁰

z = 120⁰ : 4

z = 30⁰

(y + 3)⁰ = (4z - 20)⁰

y + 3⁰ = 4 x 30⁰ - 20⁰

y + 3⁰ = 120⁰ - 20

y = 120⁰ - 20⁰ - 3⁰

y = 97⁰

5) 2x⁰ + 3x⁰ + 85⁰ = 180⁰

5x⁰ = 180⁰ - 85⁰

5x⁰ = 95⁰

x = 95⁰ : 5⁰

x = 19⁰