Start by expanding the left side of the equation: -2(4x-7) is equal to -8x + 14.
This brings you to -8x+14 = -8x + 14.
Now add 8x to both sides. This brings you to 14 = 14
Now subtract 14 from both sides. This brings you to 0 = 0.
Thus your answer is 0 = 0, which is a true statement.
Hope this helps.