Terms that have the same variable part are called like terms. Like terms can be added or subtracted to form a single term.
1.
16x - 4x = -48
First, combine the like terms 16x and -4x.
12x = -48
Now divide both sides by 12.
x = -4
2.
7m - 5 - 13m = 25
First, combine the like terms 7m and -13m.
-6m - 5 = 25
Now add 5 to both sides.
-6m = 30
Divide both sides by -6.
m = -5
3.
12.25 = 0.5q + 3.75
Subtract 3.75 from both sides.
8.5 = 0.5q
Multiply both sides by 2.
17 = q
q = 17
4.
2(2x - 4) + x = 7
Distribute the 2.
4x - 8 + x = 7
Combine 4x and x.
5x - 8 = 7
Add 8 to both sides.
5x = 15
Divide both sides by 5.
x = 3
5.
8 = 3(3x + 8) - x
Distribute the 3.
8 = 9x + 24 - x
Combine 9x and -x.
8 = 8x + 24
Subtract 24 from both sides.
-16 = 8x
Divide both sides by 8.
-2 = x
x = -2