Answer:
1761 ft²
Explanation:
The shape of the attic is a triangular prism.
It has 5 faces: The bases are 2 faces that are congruent triangles. The other 3 faces are rectangles, 2 of which are congruent.
surface area = area of the bases + area of 3 rectangles
surface area = 2 × area of triangle + 2 × area of rectangle + area of other rectangle
surface area = 2 × (1/2)bh + 2 × length × width + LENGTH × WIDTH
surface area = 2 × (1/2)(15 ft)(15 ft) + 2(15 ft)(30 ft) + (21.2 ft)(30 ft)
surface area = 225 ft² + 900 ft² + 636 ft²
surface area = 1761 ft²