7a+15b-21
-a2-8a+1
2.8a-1.4b
-234a-17
x+4y-7
10x-7y
-2x+2
-18x3+542x2+116x
7x-1
3a-3c
-2x+6y+3
-21x+15y
25x2-252x+10
-8x-9y
13
4a-11b+31
-2a-b
4x-4y
-22a5-35
-6x35-3835
4a21-821
4
84x3y4z6
15a2b2c
-192m5n5
3a4b2c32
12x3y3
-p9q5r496
32x6y7
-9m5n47
3a2
4ab
-9q2pr6
9a2
9z2x2
3c320b4
-24y2x
81x42y
2m2
xy4
-7m2n25