Evaluate
4\sqrt{5}+17\approx 25.94427191
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4\left(\sqrt{5}\right)^{2}-2\sqrt{5}+6\sqrt{5}-3
Apply the distributive property by multiplying each term of 2\sqrt{5}+3 by each term of 2\sqrt{5}-1.
4\times 5-2\sqrt{5}+6\sqrt{5}-3
The square of \sqrt{5} is 5.
20-2\sqrt{5}+6\sqrt{5}-3
Multiply 4 and 5 to get 20.
20+4\sqrt{5}-3
Combine -2\sqrt{5} and 6\sqrt{5} to get 4\sqrt{5}.
17+4\sqrt{5}
Subtract 3 from 20 to get 17.
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