Question

how to factor 15(a+2)^2+32)a+2)+16?

Answer 1

you have more right side parentheses than left ones....
that doesn't happen in math

Answer 2

oopss....15(a+2)^2 +32(a+2) +16

Answer 3

15(a+2)^2+32(a+2)+16

So,
15(a+2)^2+32(a+2)+16 = [5(a+2)+4][3(a+2)+4] = (5a+14)(3a+10)