7a+15b-21
-a2+a
1.5a-0.9
-53x2+13x
-10x-2y+2
-28a2+22a
16x+215
10x2+78x+13
-2a-11b
-x2+12x-2
5a+5b-c
10ab-15a+45b
4x-6y
-10a-27b+60
31x-2
-3x-16y-39
5x-253
2a+5b
3x4+54
11x6-5y6
4a21-821
18a5-5b
48a2bc
20x3yz43
72x3
-5a2b4c4
-72a3b4c5
-p9q5r496
-189a9b3c5
3x7y8
2a
4ab
-2x2
-3x16
3x8y2
4y3x2z
b32ac2
225c4a4b6
12xy
-4x3
-4b