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a. 3(x + 7) = 5x - 3
3x + 21 = 5x - 3
21 + 3 = 5x - 3x
24 = 2x
x = 24/2
x = 12
b. 2(7x + 1) = 3(- 2x + 4)
14x + 2 = -6x + 12
14x + 6x = 12 - 2
20x = 10
x = 10/20
x = 1/2
c. 3x - 8 = 2(- 2x + 4)
3x - 8 = -4x + 8
3x + 4x = 8 + 8
7x = 16
x = 16/7
d. - 8(2x + 1) = 5(- 3x + 4)
-16x - 8 = -15x + 20
-20 - 8 = 16x - 15x
-28 = x
x = -28
e. 2(x + 4) + 5(x + 2) = 4
2x + 8 + 5x + 10 = 4
7x = 4 - 18
7x = -14
x = -14/7
x = -2
f. - 3(x + 6) + 2(5x - 1) = 3x
-3x - 18 + 10x - 2 = 3x
10x - 6x = 18 + 2
4x = 20
x = 20/4
x = 5
g. 7(3x - 2) - 3 = -5(- 2x + 4)
21x - 14 - 3 = 10x - 20
21x - 10x = -20 + 17
11x = -3
x = -3/11
h. 6x + 2 = 3(8x - 1) - 3x
6x + 2 = 24x - 3 - 3x
2 + 3 = 21x - 6x
5 = 15x
x = 5/15
x = 1/3
