Check off all of the equations that would give no solutions

Answer:
5x + 10 = 5x - 15
6x - 8 = 2(3x - 3)
Explanation:
The equations that give no solutions are the equations that are equivalent to a false equality.
So, to find the answer, we need to solve each option:
5x + 10 = 5x - 15
5x + 10 - 5x = 4x - 15 - 5x
10 = -15 (False)
3x + 12 = 4x - 21
3x + 12 - 12 = 4x - 21 - 12
3x = 4x - 33
3x - 4x = 4x - 33 - 4x
-x = -33
x = 33
3(x + 4) = 3x + 12
3(x) + 3(4) = 3x + 12
3x + 12 = 3x + 12
5x + 10 = 6x - 8
5x + 10 - 10 = 6x - 8 - 10
5x = 6x - 18
5x - 6x = 6x - 18 - 6x
-x = -18
x = 18
2(3x - 4) = 6x - 8
2(3x) - 2(4) = 6x - 8
6x - 8 = 6x - 8
6x - 8 = 2(3x - 3)
6x - 8 = 2(3x) - 2(3)
6x - 8 = 6x - 6
6x - 8 - 6x = 6x - 6 - 6x
- 8 = - 6 (False)
Therefore, the answers are
5x + 10 = 5x - 15
6x - 8 = 2(3x - 3)