so area is 168 sq ft
That means that length * width = 168 sq ft
Since length = 10 + 2 w
we get (10+2w)(w) = 168
Multiply it out and you get 2w^2 + 10w - 168 = 0
This is a quadratic equation. You can use the formula here, but i'll just tell you the answer
w = -12, or 7
since it can't equal -12 (ever heard of a barn with a length of -12?), you figure out the answer is 7.
If the width is 7, then the length is 10+2(7) = 24.
Have a nice day!
