For each of these problems, all you need to do is isolate the variable. I’ll do the first few to help you out :)
32) 7 = -12 + e
Add 12 to both sides to isolate e.
19 = e
35) (r + 4) + 2 = 1
Subtract 2 from both sides.
r + 4 = -1
Subtract 4 from both sides to isolate r.
r = -5
38) -2 + (1 + p) = 5
Add 2 to both sides.
1 + p = 7
Subtract 1 from both sides to isolate p.
p = 6.
So essentially, all you need to do is add and subtract from each side to isolate the variable given in each problem. :)
Extra tip: In order to get rid of a number on one side (to isolate a variable), you must perform the opposite operation. For example, -2 + x = 1. In order to isolate x, add 2 to the left side to get rid of it, as well as adding it onto the right side so that it is not erased completely to get x=3)