Answer to the question

x = 48.

Step-by-step explanation:

AE and EC are equivalent. Subtract 9 from 921, and divide by 19 to get the value of x, which is 48.

the line of

hello from mrbilldoesmath!

answer:   x (x+6)^2, choice b

discussion:

factor x out of the equation:

x^3 + 12x^2 + 36x = x (x^2 + 12x + 36).

note that 6+6 = 12 and 6*6 = 36 so the above factors into:

x (x+6)^2

which is choice b

you,

mrb