Kayla used 4 isosceles triangles and one square to build a pyramid each edge of the square was 10 inches the two congruent sides of the triangles are 13 inches long the slant height of the triangles is 12 inches why is the surface area of a figure
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Kayla constructed a square pyramid.
The area of the square is 10*10 = 100.
The area of each of the triangles are 12*5/2 = 30.
In total, we get 30*4 + 100 = 220.