Question

Question #02ef3

Answer 1

I found:
`r=4.2`in.
`d=8.4`in

Explanation:

Remember that the area is: `pir^2` so using your given value you get:
`18pi=pir^2`
rearranging:
`r^2=18pi/pi=18`
`r=sqrt(18)=4.2`in.
The diameter is twice this value; or:

`d=2r=2xx4.2=8.4`in

Answer 2

`"Radius"=3sqrt2`

`"Diameter"=6sqrt2`

Explanation:

We know that the area of the circle is `18pi`. We need to find the radius and the diameter.

For that, we use the formula

`color(BLUE)("Area of circle"=pir^2`

Where `r` is the radius of the circle

So,

`rarrpir^2=18pi`

Divide both sides by `pi`

`rarr(cancelpir^2)/cancelpi=(18cancelpi)/cancelpi`

`rarrr^2=18`

Take the square root of both sides

`rarrsqrtr^2=sqrt18`

`rarrr=sqrt(9^2)`

`color(purple)(rArrr=3sqrt2~~4.24`

Now, we need to find the diameter

As the diameter is twice the radius,

`color(darkviolet)(rArr"diameter"=2*3sqrt2=6sqrt2~~8.48`