Posted a picture showing the solution. Everything is on it, including calculations.
The answer is 142 square inches (or 142 in.^2) same thing.
Hope this helps!
Both A and C are used within this problem. Distributing happens in the first and second step. Also, Inverse operations are used in nearly every step that is solving.
I am thinking of a rectangle that has the two sides parallel to one another. Set the two functions equal to one another, so
9x-14=7x+4
After a bunch of algebra and math magic, 2x=18 => x=9
So if you just insert 9 into both equations, both will end up with a value of 67, so it ends up looking like a right triangle. Don't do that. Instead, to find the rectangle widths, use 9x-4 (+10 added to intercept) instead, while keeping 7x+4, so that the intercepts match.
LN) 9x-4 = 9(9)-4 = 81-4 = 77
MP) 7(9)+4 = 63+4 = 67
*If you are also looking for the diagonals, use Pythagorean Theorem 77^2+67^2=(hypotenuse)^2*
