I'm assuming that when you wrote "(7x/2-5x+3)+(2x/2+4x-6)," you actually meant "<span>(7x^2-5x+3)+(2x^2+4x-6). Correct me if I'm wrong here.
</span><span>+(7x^2-5x+3)
</span><span>+(2x/2+4x-6)
-------------------
=9x^2 - x - 3 (answer) </span>
This is how I did it, I really hope it helped you with your homework
If you mean width, 7 x 7 = 49, so 49 feet, then add on the 3.5 feet due to the 0.5 left over, and you have 52.5
X=-2 is the answer to your question.
That would be the one and only 22