How do you solve for x?
-3x + 7 = 28
4.5x - 7 = 20
2x + 3 = -7

1.)
-3x + 7 = 28
We need to get -3x by itself and then simplify.
Subtract 7 from both sides.
7 - 7 = 0
28 - 7 = 21
Now we have:
-3x = 21
Divide both sides by -3.
-3x / -3 = x
21 / -3 = -7
x = -7

2.)
4.5x - 7 = 20
Add 7 to both sides.
4.5x = 27
Divide both sides by 4.5.
4.5x / 4.5 = x
27 / 4.5 = 6
x = 6.

3.)
2x + 3 = -7
Subtract 3 from both sides.
3 - 3 = 0
-7 -3 = -10
2x = -10
Divide both sides by 2.
2x / 2 = x
-10 / 2 = -5
x = -5.

I hope this helps!