15a
-a2+a
2.8a-1.4b
-45a2-2a
-2x2+3x+4
10x-7y
-16x2-16x+56
218x-218y
-2a+14
11a+16b-4c
2ab+15a-17b
30x2-35x
3x-2
18a+115b-27
13
6x-25y
-34x+32
-6x+23y
7m3+83
-11x72+41y72-3172
11a20+47b20
x-2
84x3y4z6
-6m3n4
-168a5b3
-m6n72
-72a3b4c5
200x5
2a4b4c47
3a9b8c420
3a2
2pq23r2
-5x3y
-8y23x2
9z2x2
6ab
-24y2x
c29a4b4
10x
m6n24
-4p3r3