Answer:
x = -6
Explanation:
Subtract the right side, simplify, divide by the x-coefficient.
4(x -3) +54 +3x = 0
4x -12 +54 +3x = 0 . . . . eliminate parentheses
7x +42 = 0 . . . . . . . . . . combine terms
x +6 = 0 . . . . . . . . . . . . . divide by 7
x = -6 . . . . . . . . . . . . . . . add the opposite of the constant