Question

Which circles have an area of 9pi m2? Choose all answers that are correct. A. a circle with a radius of 3 m B. a circle with a diameter of 6 m C. a circle with a radius of 9 m D. a circle with a diameter of 9 m. Multiple Choice Question!

Answer 1

The formula of the area of a circle is
A =
`\pi`r²
given the area, find the radius

9
`\pi` m² =
`\pi`r²
Divide by
`\pi`


`\pi` cancels out on both sides

9 = r²
Take square root on either sides

`√(9)` =
`√(r^2)`
3 m = r
The radius = 3 meters
Be careful for the units given
Its METERS

A. A circle with radius of 3 m
B. A circle with diameter of 6 m
(diameter = 2×radius, 2 × 3 = 6)