Question

What is the geometric mean of 7 and 12? a.1b.9.5c.2√21d.4√21

Answer 1

To find the geometric mean,

Simply follow the steps below:

`\frac{x}{7\text{ }}=(12)/(x)`
`x^2=84`

Take the square root of both-side

`x=\sqrt[]{84}`
`=\sqrt[]{4\text{ x 21}}`

`=2\sqrt[]{21}`

Therefore, the correct option is C.2√21