Question

How do you solve for x?

-3x + 7 = 28

4.5x - 7 = 20

2x + 3 = -7

Answer 1

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!

Answer 2

These are two-step equations. The first step is to isolate the term with the variable, so you will add/subtract the constant term on both sides. Then, multiple/divide by the coefficient of x on both sides. Don't forget dividing with negative rules: Like signs positive, unlike signs negative.
-3x+7=28 subtract 7
-3x=21 divide by -3
x=-7

4.5x-7=20 add 7
4.5x=27 divide by 4.5
x=6

2x+3=-7 subtract 3
2x=-10 divide by 2
x=-5