Answer: D
Explanation:
A. 2(2x + 1) = 4x + 2
4x +2 = 4x +2 because it's the same on both sides you have infinite answers
B. 3x + 7 = x
2x= -7
x = -7/2 one answer
C. 3x + 6 = x + 2
2x = -4
x= -4/2 = -2 one answer
D. 5x + 1 = 5x - 3 if you bring 5x over it cancels out
1 = -3 this is what you are left with and it's not true so this one has no solution