Jusitn's Surface Area Growing Post

TSA of rectangular prism

The rectangular prism has rectangular faces.

So, use the formula A = lw to find the area of the faces.

For both the front and back faces, l = 5 in. and w = 2 in.

So, the area of the front and back faces is,

5 2 2 = 20 in.²

For both the top and bottom faces, l = 14 in. and w = 5 in.

So, the area of the top and bottom faces is,

14 5 2 = 140 in.²

For both the sides, l = 14 in. and w = 2 in.

So, the area of the two sides is,

14 2 2 = 56 in.²

Add the area of the faces.

20 + 140 + 56 = 216

So, the total surface area of the given solid is 216 in.².

TSA of triangular prism

The triangular prism has triangular bases.

So, to find the area of the bases, use the formula:

Substitute 6 for b and 8 for h.

Therefore, the area of the two bases is,

2(24) = 48 cm²

The triangular prism has rectangular sides.

So, use the formula A = lw to find the area of the sides.

The area of the front side is,

13 8 = 104 cm²

The area of the bottom side is,

13 10 = 130 cm²

The area of the back side is,

13 6 = 78 cm²

Find the sum of the base areas and the area of the sides.

48 + 104 + 130 + 78 = 360

So, the total surface area of the given solid is 360 cm².

TSA of a cylinder

The radius of the circular base is,

he area of a circle is, A = πr² where r is the radius.

Replace π with 3.14, r with 2.4.

A (3.14)(2.4)²

A = 18.0864

So, the area of one base is 18.0864 cm².

The sum of the areas of the two bases is,

18.0864 + 18.0864 = 36.1728 cm²

This video is on how to find the tsa of a cylinder , rectangular prism, and triangular prism. It was created by Warren, Bruce and I.