Question

How do i expand (3x+5)^2

Answer 1

I don't know how you expand it but the answer is 3x + 25 unless that's expanding.

Answer 2

(3x + 5)^2 expands into two binomials: (3x + 5)(3x +5)

from there, you foil them:
(3x + 5)(3x + 5)
multiply the first terms ... 9x^2
the inside terms ... 9x^2 + 15x
outside terms ... 9x^2 + 15x + 15x
last terms ... 9x^2 + 15x + 15x + 25
then add like terms ... 9x^2 + 30x + 25

that's the expanded binomial!!