Find the exact length of the diagonal of this figure if length is 8, width is 4 and height is 2. Show all your work for full credit.

Question

Find the exact length of the diagonal of this figure if length is 8, width is 4 and height is 2. Show all your work for full credit.

Answer 1

a little less than 9.2 = the diagonal of the 2x4x8 box

find the diagonal of the bottom side, d^2 = 8^2+4^2 = 64=16 = 80

diagonal of the bottom side = sqr80

now find the diagonal of the box itself with sqr80 as the base and 2 as the height of a right triangle with d=sqr(80+4) = sqr84 = about 9.2