The cross section is just a rectangle. So to work out the area, multiply the length of the base together by the height.
This is 22 x 12 = 264cm²
Since this is a right triangle, you can use the pythagorean theorem,
, to find XY. Since we know that 15 and 17 are our legs and that XY is the hypotenuse, we can solve it as such:

In short, XY is √514, or 22.67 rounded to the hundreths, units long.
Answer:16
Step-by-step explanation:The lines that are outside of the numbers keep the numbers positive so if you change them to positive number (15+1) you can add them and it gives you 16