Answer:
75 in²
Step-by-step explanation:
From the diagram, you can see that the shape is made up of a square and 4 triangles. (We know it's a square as the width = length).
First, find the area of the square.
Area of a square = width x length = 5 x 5 = 25 in²
All the triangles are the same, so we need to find the area of one of the triangle and multiply it by 4.
Area of a triangle = x base x height = x 5 x 5 = 12.5 in²
So total area of 4 of these triangles = 4 x 12.5 = 50 in²
Therefore the total surface area = 25 + 50 = 75 in²