Answer:
a.
1. 40x9
2. b2+4b+4
3. 6m3n2−42mn−9m2n+63
4. −21x3+28x2−63x
5. 2m2−13mn+15n2
6. 2b3+b2−11b+12
b.
1. 2t6+0t5+0t3
2. 7r5+0r4+2r3
3. d3+0d2+0d+9f2−5
4. 2x−7
Step-by-step explanation:
hope it helps
