Answer:
(x+3)²
Step-by-step explanation:
1) Expand the square.
(x+3)²
(x+3)(x+3)
2) Distribute.
(x+3)(x+3)
x(x+3)+3(x+3)
3) Distribute.
x(x+3)+3(x+3)
x² + 3x + 3x + 9
4) Combine like terms.
x² + 3x + 3x + 9
x²+6x+9
5) Use the sum-product pattern.
(x+3)²
x²+3x+3x+9
6) Common factor from the two pairs.
x²+3x+3x+9
x(x+3)+3(x+3)
7) Rewrite in factored form.
x(x+3)+3(x+3)
(x+3)(x+3)
8) Combine to a square.
(x+3)(x+3)
(x+3)²
