The answer is 21.
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Answer:

Step-by-step explanation:
We want to simplify:

We rewrite as:

We split the radical sign to obtain:

Simplify the square root for the perfect squares to get:

Therefore the simplified form is: 
Answer: No, the answer is 29, this is false.
Step-by-step explanation: 63-x=34
subtract 63 from both sides
34-63= -29
-x=-29
divide both sides by the negative and you get 29
plug in 29 for x, 63-29=34
300.02 if you use the square root of 72