Question

Two same-sized triangular prisms are attached to a rectangular prism as shown below.

If a = 20 cm, b = 13 cm, c = 12 cm, d = 5 cm, and e = 8 cm, what is the surface area of the figure?
a 1,208 square centimeters
b 1,592 square centimeters
c 1,004 square centimeters
d 1,400 square centimeters

Answer 1

A*E*2= 20*8*2=320
A*C*2= 20*12*2=480
D*C/2*4 5*12*2=120
B*E*2 13*8*2=208
D*E*2 5*8*2=80
320+480+120+208+80=1208
so ur answer is A

Answer 2

Answer: a) 1,208 square centimeters

Explanation:

The surface area would be the sum of the different areas separated in the figure.

The area of the front and back faces of the rectangular prism:

`a*c*2=20*12*2=480cm^(2)`

The area of the top and the base of the rectangular prism:

`a*e*2=20*8*2=320cm^(2)`

The area of the front and back faces of both triangular prisms:

`(d*c)/(2)*4=(5*12)/(2)*4=30*4=120cm^(2)`

The area of the side faces of both triangular prisms:

`e*b*2=8*13*2=208cm^(2)`

The area of the bases of both triangular prisms:

`d*e*2=5*8*2=80cm^(2)`

Finally, the surface area of the whole figure:

`480+320+120+208+80=1,208cm^(2)`