Question

Hi there, can someone please help me with my math homework. It’s only the blue highlighted sums I need. Please help I’ll really appreciate it.

Answer 1

Answer:

(15)

$-mn(2m+7n)$

(16)

$x^{3}$

(17)

$9x^{3}$

(18)

$6x^{5}$

(19)

$21m^{5} n^{3}$