Can someone explain this t me im lost

166

I don't know how to explain it because i used a special Surface Area calculator

The equation for surface area is A=2(wl+hl+hw) , so step by step

L=7

w=5

h=4

2(wl) +2(hl)+ 2(hw) = 2(7x5) + 2 (4 x 7) + 2 ( 5 x 4)

                               = 2 (35) + 2 ( 28) + 2 ( 20)

                              = 70 + 56 + 40

                              = 166

so the surface area would be 166

explanation:

previous steps have made pa≅ pb ≅ st ≅ su. setting the compass width to ab allows you to make tu the same length. then δstu ≅ δpab by the sss congruence postulate, and ∠p ≅ ∠s by the reason cpctc.