Evaluate
2\left(\sqrt{7}+1\right)\approx 7.291502622
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2+3\sqrt{7}-\sqrt{7}
Factor 63=3^{2}\times 7. Rewrite the square root of the product \sqrt{3^{2}\times 7} as the product of square roots \sqrt{3^{2}}\sqrt{7}. Take the square root of 3^{2}.
2+2\sqrt{7}
Combine 3\sqrt{7} and -\sqrt{7} to get 2\sqrt{7}.
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