Question

If 2x − 4(x + 1) = −12, evaluate x2 − 1.

Answer 1

2x-4(x+1)=-13
1) we solve this equation:
2x-4(x+1)=-12
2x-4x-4=-12
-2x=-12+4
-2x=-8
x=-8/-2
x=4

2) we evalute x²-1
x²-1=4²-1=16-1=15

Answer: 15