A triangular pyramid and its net are shown. Rain uses the calculations below to conclude
that the surface area of the triangular pyramid is 238.5 square inches.
3({ x 10 x 13) + (1 x 10 x 8.7)
3 (65) + 43.5
238.5
Is Rain correct? Use the drop-down menus to explain your reasoning.
12 in
12 in
13 in
13 in
8.7 in.
12 in.
10 in
10 in
10 in