Total Surface Area of Rectangular Prism

Each side of a rectangular prism is called a face.

A rectangular prism has six faces.

In a rectangular prism there are 3 pairs of opposite and equal sides.The first pair is the red face

7 cm (l)

4 cm (b)

10 cm (h)

10 cm (h

7 cm (l)

We can see another face - just like the red face. That is on the back.

7 cm(l)

10 cm(h)

7 cm(l)

10 cm(h)

Now there are 2 rectangles that each have an area of 70cm² ie lh+lh=2lh

l x h= 7 x 10= 70cm² 70 cm

2

70 cm

2

The second pair is the blue face

10 cm (h)

4 cm (b)

7 cm (l)

4 cm (b)

10 cm (h)

We can see another face - just like the blue face. That is on the left side.

10 cm (h)

4 cm (b)4 cm (b)

10 cm (h)

Now there are 2 rectangles that each have an area of 40cm² ie bh+bh=2bh

40cm²

40cm²

b x h= 4 x 10= 40cm²

The third pair is the green face

10 cm (h)

4 cm (b)

7 cm (l)

7 cm (l)

4 cm (b)

We can see another face - just like the green face. That is on the bottom.

4 cm (b)4 cm (b)

7 cm (l) 7 cm (l)

Now there are 2 rectangles that each have an area of 28cm² ie lb+lb=2lb

28cm²

28cm²

l x b= 7 x 4= 28cm²

Now we just need to add all the areas of the sides together.

+ +

++28cm

2

40cm

2

70cm

2 70cm

2

40cm

2

28cm

2

The total surface area for this rectangular prism is

70+70+40+40+28+28=276 cm²

Ie2lb+ 2bh+ 2lh

The Lateral surface area for this rectangular prism is

L.S.A = 2lh + 2bh

Find the T.S.A and L.S.A of a rectangular prism.

Find the T.S.A and L.S.A of a rectangular prism with length =9cmbreadth=6cmheight = 12cm