GCF HELP PLEASE....?

Question

7. Factor.

5x^3 + 25x

A. 5(x^3 + 5)

B. 5x(x^2 + 1)

C. 5x(x^2 + 20)

D. 5x(x^2 + 5)

8. Factor.

18a^4b^7 - 12a^2b

A. 12ab(2a^3b^6 - a)

B. 6a2(3ab^7 - 2a)

C. 6a2b(3a^2b^6 - 2)

D. 6a4b(3ab^6 - 2)

Answer 1

D, because you do 5x^2 *5x = 5x^3, +25x (use the distributive property). By adding the powers when you multiply, x^2 * x (2+1), you get x^3.

C because 6a^2 *3a^2 = 18a^4, then 2b*2b^6 which gives you 2b^7, because when you multiply exponents, you are adding the powers (1 +6)  and 6a^2b*2 = 12a^2b

Again, use the distributive property, and multiply the common exponents.