From the Pythagorean Theorem, we know that a^2+b^2=c^2
28^2+21^2=(5x)^2
784+441=25x^2
1225=25x^2
49=x^2
x=7
The length of the hypotenuse would be 35m.
He would need to at least 44 to sell before breaking even.
Multiply the number together ....
(-3x)4 = -12x
The answer is A the first choice