Evaluate
69-16\sqrt{5}\approx 33.22291236
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69-16\sqrt{5}
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64-16\sqrt{5}+\left(\sqrt{5}\right)^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(8-\sqrt{5}\right)^{2}.
64-16\sqrt{5}+5
The square of \sqrt{5} is 5.
69-16\sqrt{5}
Add 64 and 5 to get 69.
64-16\sqrt{5}+\left(\sqrt{5}\right)^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(8-\sqrt{5}\right)^{2}.
64-16\sqrt{5}+5
The square of \sqrt{5} is 5.
69-16\sqrt{5}
Add 64 and 5 to get 69.
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