Question

How do you find the area of a circle with radius 3 inches?

Answer 1

Area `= 9pi ~~28.27433`

Explanation:

The area of a circle is given by the formula
`color(white)("XXX")A = pir^2`
where `A` is the area of the circle,
`color(white)("XX")r` is the radius of the circle, and
`color(white)("XX")pi` is a standard constant (approximately `~~ 3.14159`)

So with `r=3`
`color(white)("XXX")A = pi*3^2 = pi*9 or 9pi`