Question 294812
A) Square root of 45  x square root of 20
= {{{sqrt(45*20) = sqrt(900)}}}
= 30, or -30
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b) Square root of 45 + square root of 20
{{{sqrt(45) = sqrt(9)*sqrt(5) = 3sqrt(5)}}}
{{{sqrt(20) = sqrt(4)*sqrt(5) = 2sqrt(5)}}}
--> {{{5sqrt(5)}}}
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c) Square root of 45 - square root of 20
= {{{sqrt(5)}}}