Question

find the geometric mean of 7 and 9. a. $3sqrt{7}$ b. $sqrt{70}$ c. $6sqrt{2}$ d. 63 please select the best answer from the choices provided. a b

Explanation:

Step1: Recall geometric mean formula

For 2 numbers $a,b$, mean = $\sqrt{a \times b}$

Step2: Substitute $a=7, b=9$

$\sqrt{7 \times 9} = \sqrt{63}$

Step3: Simplify the radical

$\sqrt{63} = \sqrt{9 \times 7} = 3\sqrt{7}$

Answer:

A. $3\sqrt{7}$