How do you simplify sqrt(14) times sqrt(21)?

Jul 2, 2016

$7 \sqrt{6}$

Explanation:

Break each number down into its prime factors first,
Then combine the two roots into one and see where we go from there....

$\sqrt{2 \times 7} \times \sqrt{3 \times 7} = \sqrt{2 \times 3 \times 7 \times 7}$

= $\sqrt{6 \times {7}^{2}} = 7 \sqrt{6}$