To do this you would first find the area of the 2 triangles shown on the side so we would do 5 times 2 divided by 2 since that is how we solve this problem so we would get 5 inches squared for the 2 triangles then we would find the area of the square which is 100 since it is a 10 by 10 then you would subtract 5+5 by 100 which is 90 so 90 inches squared would be the answer