Answer:
D. 25x² - 20x + 4
Step-by-step explanation:
The formula for the area of a square is: A = s², where s = a side length of the square since all side lengths of a square are equal. In this case, the side length is represented by '5x', so the original area is A = (5x)² = 25x².
Since Kelly is cutting off one inch from each side of square, this will actually take off 2 total inches from each side, making the new side length '5x - 2'. We can now put this expression in for the values of 's' in our formula for area and use distributive property to solve:
A = (5x - 2)² = (5x - 2)(5x - 2)
Distribute using FOIL: 25x² - 10x - 10x +4 or 25x² - 20x + 4
