Answer:
Hello! answer: 39
Explanation:
Formula for triangles area: base × height ÷ 2
Formula for squares area: base × height
5 × 3 = 15 15 ÷ 2 = 7.5 since there are 4 triangles that are the exact same I will just multiply by 4 so I have all the triangles so 7.5 × 4 = 30 now the square is just 3 × 3 so... 3× 3 = 9 now we add these up 30 + 9 = 39 therefore the surface area is 39