The perimeter of a rectangle is 20 cm. the length is 7 cm. what is the area?

Hey there!

So we know the perimeter is 20 cm. Let's make our formula for this.

2L + 2W = 20

The formula for the area of a rectangle is L x W. Let's make this into our formula and fill it in as time goes.

L x W

Our Length is measured at 7 cm, so let's fill that into our formulas.

2(7) + 2W = 20
7 * W = x

Let's use some basic algebra to solve for our perimeter.
2(7) + 2W = 20
14 + 2W = 20
2W = 6
W = 3

This means our Width is 3. Now all we have to do is solve for our area since we have our dimensions.

7 x 3 = 21

The area of the rectangle is 21 cm^2.

I  hope this helps!

Ithink you're supposed to multiply 12.50 which is how much he makes per hour and then multiply it by each number then add whats left togrther and there's your answer