Question

Calculating the Surface Area of a Triangular Prism The triangular prism shown has 1235 triangular face(s) and 1235 lateral face(s). The area of one triangular face is 7.58.1251517 mm2. The surface area of the triangular prism is 55.5127.5135150 mm2.

Answer 1

A....2

B....3

C.....7.5

D......135

Explanation:

Answer 2

Corrected Question

The triangular prism shown has 1, 2, 3 or 5 triangular faces and 1,2,3, or 5 lateral faces.

The area of one triangular face is 7.5,8.125,15,or 17
`mm^2`

The surface area of the triangular prism is 55.5,127.5,135,or 150
`mm^2`

Answer:

(B)2 triangular faces

(C)3 lateral faces.

(A)Area of one Triangular Face
`=7.5mm^2`

(C)Total Surface Area of the Triangular prism
`=135mm^2`

Explanation:

The triangular prism is attached.

The triangular prism shown has 2 triangular faces and 3 lateral faces.

Base of the triangle =2.5mm

Height of the Triangle =6mm

Area of one Triangular Face
`=(1)/(2)*6*2.5=7.5mm^2`

The dimensions of the lateral rectangles are:

• 2.5 mm by 8mm
• 6 mm by 8mm
• 6.5 mm by 8mm

Therefore, total surface area of the triangular prism

=2(Area of one Triangular Face)+Area of 3 rectangular faces

`=2(7.5)+ (2.5 X 8+ 6 X 8 + 6.5 X 8)\\=15+120\\=135mm^2`

Total Surface Area of the Triangular prism
`=135mm^2`