The answer is C) 300 square feet
The way I figured this out is because by having the diagonal it is the same as cutting a rectangle in half , it forms a triangle and by using the Pythagoras therom I found the left over side
The hypotenuse was 25 and one the sides was 20
so...
25 ^ 2 - 20^2 = x ^2
625 - 400 = x^2
225 = x^2
15= x
So now that I had one of the sides I took that and multiplied it by the base to find my area
15 * 20 =300
And that is how I got the answer
I really hope everything I explained make sense