Answer:
2). 2r+8-r=-7
r+8=-7
-8 -8
r=-15
3). -9a-3a=36
-12a=36
divide by 12 on both sides
a=-3
4). 5x+4x-27=81
9x-27=81
+27 +27
9x=108
divide by 9 on both sides
x=12
5). 2n+3n+7=-43
5n+7=-43
-7 -7
5n=-50
divide by 5 on both sides
n=-10
6). 3h-5h+11=17
-2h+11=17
-11 -11
-2h=6
divide by -2 on both sides
h=-3
7). 2k-6+3k=14
5k-6=14
+6 +6
5k=20
divide by 5 on both sides
k=4
8). x+24-9x=-8
-8x+24=-8
-24 -24
-8x=-32
divide by -8 on both sides
x=4
9). 19a-12-4a=-57
15a-12=-57
+12 +12
15a=-45
divide by 15 on both sides
a=3
10). 2x-5x+63=-14.4
-3x+63=-14.4
-63 -63
-3x=-48.6
divide both sides by -3
x=-16.2