first you have 2 triangles and 3 rectangles so you will get the area of 5 of them
for the first face of rectangle
2.5x10=25
second face
2x10=20
for the third rectangle which is the base
10x1.5=15
for the two triangles
1/2xBasexHeight
1/2x1.5x2=1.5 ——> this is for one triangle so multiply by 2 to get both triangles
1.5x2=3
so the total surface area is equal to 3+25+20+15=63