The correct answer for the problem above is -23 .
Explanation
1. collect the like terms
2x + x - 11 + 3 - 7x = 15
2x , x , & -7x are like terms
-11 & 3 are like terms
2x + x -7x = -4x
-11 + 3 = -8
2. Move constant to the right-hand side and change its sign .
-4x = 15 + 8
-4x = 23
3. Make the signs on both sides of the equation
-4x = 23 turning into 4x = -23
answer =
4x = -23