Answer:
A = 9x² + 48x + 65
Step-by-step explanation:
Area of a Square Formula: A = lw
Since a square's length is equal to its width, we simply plug it into the formula:
A = (3x + 8)(3x + 8)
Then we simply use FOIL to expand the distribution)
First - 3x(3x) = 9x²
Outside - 8(3x) = 24x
Inside - 8(3x) = 24x
Last - 8(8) = 64
Lastly, we combine like terms
9x² + 24x + 24x + 64
9x² + 48x + 64
