Net of a triangular prism sides 6, 8, 10, length 5

Step by step

The question

Question: draw the net of a triangular prism, sides 6, 8, 10, length 5, and find its surface area.

The surface area is the area of all the outside faces together.

A net shows every face flat.

1 Unfold it

Flat: three rectangles in a row, and a triangle at each end.

2 Area of each face

The two triangles: half × 6 × 8 is 24.

The 6 by 5 rectangle: 6 × 5 is 30.

The 8 by 5 rectangle: 8 × 5 is 40.

The 10 by 5 rectangle: 10 × 5 is 50.

Careful!

Count every face in the net.

There are two triangles, one at each end.

3 Add them all

We add all 5 faces: 168.

4 Check

Let's check another way.

The three rectangles make one long strip: 24 by 5, that is 120.

Plus the two triangles, 48.

Together 168.

So the answer is right!

Let's look back.

First: unfold it.

Then: area of each face.

Then: add them all.

Last: check.