Respuesta :
Answer:
-1/3 sqrt(21)
Step-by-step explanation:
1/3 sqrt(21) - 2/3 sqrt(3) * sqrt(7)
We know sqrt(a) * sqrt(b) = sqrt(ab)
1/3 sqrt(21) - 2/3 sqrt(21)
Factor out sqrt(21)
sqrt(21) (1/3-2/3)
sqrt(21) (-1/3)
-1/3 sqrt(21)
Answer: Choice A) [tex]-\frac{1}{3}\sqrt{21}[/tex]
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Work Shown:
I'm guessing that the x you wrote is to signify multiplication. If so, then one way to do the steps is shown in the attached image below.
In step 2, I used the rule that sqrt(x)*sqrt(y) = sqrt(x*y).
