2018 AMC 10A Problems/Problem 10
Suppose that real number satisfies . What is the value of ?
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[hide]Solutions
Solution 1
In order to get rid of the square roots, we multiply by the conjugate. Its value is the solution.The terms cancel nicely.
Given that = 3,
Solution by PancakeMonster2004, explanations added by a1b2.
Solution 2 (bad)
Let , and let . Then . Substituting, we get . Rearranging, we get . Squaring both sides and solving, we get and . Adding, we get that the answer is
See Also
2018 AMC 10A (Problems • Answer Key • Resources) | ||
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Followed by Problem 11 | |
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