kak tolong ya.... besok dikumpulkan ..

a. 45 + x = 180
x = 180 - 45
× = 135

b. 3x + 60 = 180
3x =120
x = 40

3× = 3×40= 120

c. 7x + 2x = 90
9x = 90
× = 10

7× = 7×10 = 70
2× = 2× 10 =20

d. 6x + 4x +30 = 90
10 x = 90 - 30
10x = 60
x = 6

6x = 6×6 = 36
4x = 4×6= 24

e. x + 35+ 2× +3× +80 = 180
6× + 115 = 180
6× = 65
× = 10.83