salinlah gambar berikut kemudian tentukan besar sudut yang belum diketahui

a + 70 = 180
a = 180 - 70
a = 110

a + b = 180
110 + b = 180
b = 110 - 110
b = 70

c = a = 110

d + 138 = 180
d = 180 - 138
d = 42

e = 138

f = d = 42

p + 52 = 180
p = 180 - 52
p = 128

q = 52

r = p = 128

x + 100 = 180
x = 180 - 100
x = 80

y = 100

z = x = 80