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5(2x-7) + 3(4x-7) - (x+2) = -142
Put a 1 before the (x+2)
5(2x-7) + 3(4x-7) - 1(x+2) = -142
Distribute:
10x - 35 + 12x - 21 - 1x - 2 = -142
Combine 10x + 12x - 1x to get 21x
Combine -35 - 21 - 2 to get -58
                    21x - 58 = -142
Add 58 to both sides:
                         21x = -84
Divide both side by 21
                    21x/21 = -84/21 
             
                         x = -4
Edwin