7 (4 + 3x) = 45 (x - 3) - 3 (2x - 12)

7 (4 + 3x) = 45 (x - 3) - 3 (2x - 12)

Distribute:

28 + 21x = 45x - 135 - 6x + 36

Collect like terms:

28 + 21x = 39x - 99

Rearrange terms to get them all on one side (add 99 to both sides):

28 + 99 + 21x = 39x - 99 + 99

Simplify:

127 + 21x = 39x

Subtract 21x from both sides:

127 + 21x - 21x = 39x - 21x

Simplify:

127 = 18x

Divide by 18 on both sides to isolate the x variable and solve the expression:

127/18 = 18x/18

Simplify:

x = 127/18