How do you simplify sqrt3*3sqrt21?

2 Answers
FRANK Z.
May 17, 2018

9sqrt(7)

Explanation:

As you multiply roots, then the equation can become
3sqrt(63)
but we can take out the 3, making it
9sqrt(7)

Jim G.
May 17, 2018

9sqrt7

Explanation:

"using the "color(blue)"law of radicals"

•color(white)(x)sqrtaxxsqrtbhArrsqrt(ab)

rArrsqrt3xx3xxsqrt21=3xxsqrt(3xx21)=3sqrt63

3sqrt63=3(sqrt(9xx7))=3(sqrt9xxsqrt7)=3(3sqrt7)=9sqrt7

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