Question

Find the area of the circle. Use 3.14 for pi. Round to the nearest unit. A circle has a diameters of 18 centimeters. A. 1,017 cm2 B. 254 cm2 C. 57 cm2 D. 28 cm2 2 / 5

Answer 1

B. 254 cm²

Explanation:

Hello!

Circle

The formula for the area of a circle is
`A = \pi r^2`

• A is area
• π is pi (roughly 3.14)
• r is the radius

The radius is half of the diameter, given with the formula
`D = 2r`

Area

Using the information, we can first solve for the radius.

• 
  `D = 2r`
• 
  `18 = 2r`
• 
  `9 = r`

The radius is 9

Now we can plug 9 into the area formula:

• 
  `A = \pi r^2`
• 
  `A = \pi (9^2)`
• 
  `A = 81\pi`

We are going to use 3.14 for pi

• 
  `A = 81(3.14)`
• 
  `A = 254.34`

The area is 254.34cm².

We are going to round to the nearest whole centimeter, which is roughly 254cm² or
`\boxed{\text{Option B}}}`