Simplify: 656×613
676
6518
669
3676
Simplify: 4x-36x4
23x12
23x7
1384x7
-323x
x2·x4=
x8
8x
x6
6x
5y-4=
15y4
-20-4y
5y4
12781214=
158
1272
1258
1298