Here's the question you clicked on:
qwertyfreak
Find the length of the diagonal of the rectangle. The rectangle is 12in by 7in. the 12in parts are top and bottom, 7in parts are the sides. The line is diagonal from the top left corner to the bottom right corner. 13.0 in 13.4 in 13.6 in 13.9 in
Heres what it looks like: |dw:1335534654241:dw| but of course straight lines
this is just an application of the pythagorean theorum
what is the sum of the squares of the sides? 12^2 + 7^2 = ?
good, then the last part is to take the sqrt of that \[diag=\sqrt{193}\]
13.892444 so my answer is 13.9