Question

simplify by factoring.
\[\sqrt{90}\]
i get 3√10

Answer 1

sqrt90 = sqrt9 * sqrt 10

you are correct

Answer 2

√10=√2√5

Answer 3

we think of number that go into 90 that give is a 'nice ' square root that we can work out easily with no decimals if possible
by 'nice' square roots we mean
\[\sqrt{4},\sqrt{9},\sqrt{16},\sqrt{25}.....\]
these numbers are called 'square numbers because you can form a square out of 4 dots, 9 dots, 16 dots etc...so
\[\sqrt{90}=\sqrt{9}\sqrt{10}=3\sqrt{10}\]