Examine the composite figure formed by placing a triangular prism on top of a rectangular prism. All of the measurements have centimeters as their units.
The triangular base has height 12, base 14 & 2 other sides 13 & 15. The prism height is 20. The rectangular prism is 8 by 14 by 20. The prisms share a face that is 14 by 20.

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To find the surface area, Brad splits the figure into two pieces, the rectangular prism and the triangular prism.

He finds the total surface area of the rectangular prism by finding the area of each face to get 1,104 cm2.
He then finds the total surface area of the triangular prism by finding the area of each face to get 1,008 cm2.
Finally, he adds the surface areas together to get 2,112 cm2.
Is Brad's solution correct? Why or why not?