The area of the base that is a square is 25 square inches. Now let's take a look at the triangles. Note that sides of the pyramid are congruent triangles. This means that they have the same area. Let's substitute the measures of the sides into the formula for the area of a triangle!
We found that the area of one triangle is 13.75 square inches. Since the triangles are congruent, that means that the area of every triangle is 13.75 square inches. Now we have all the information that we need to find the total surface area of the square pyramid!
Total Surface Area
25+ 13.75+ 13.75+ 13.75+ 13.75=80in.^2
The total surface area of the square pyramid is 80 square inches.