# algebra

Simplify: sqrt (21) (sqrt(7) + sqrt(3))

a) 7 sqrt (3) + 3 sqrt(7)
b) 7 sqrt(3) + sqrt (3)
c) sqrt (210)
d) sqrt (147) + sqrt (63)''.

a

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1. √21√7 + √3
= √3√7√7 + √3
= 7√3+√3
= 8√3

the answer matching this is b)
but they should have simplified this.

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2. thanks reiny

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