The area of a rectangle is Base x height whereas the area of a triangle is Base x height divided by 2
the surface area of that rectangular prism is 247.5.
If you cut the rectangle (the wall) diagonally, you get two congruent triangles. The measurements of the sides of one the triangles is 8, 15 and x. There is a pythagorean triples 8, 15, 17 so x has to be 17. if you dont know the triple you can do a^2 + b^2 = c^2 8^2 + 15^2 = c^2 c = 17
the diagonal of wall should be 17
