Question

Find the square roots of 900

Answer 1

30

Answer 2

I assume you don't have a calculator!? You could type
sqrt(900)=
in Google's search window.

If you wanted to do this in your head, think of it as sqrt( 9 * 100)= sqrt(9)*sqrt(100)
Of course sqrt(9)= 3, and the square root of 100 is 10, so you get 30.
Also, the question asks for the roots (plural), so you also want -30.