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2007 AMC 10A Problem 20

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2007 AMC 10A Problem 20AMC 10 Step by Step
Name:                             Date: September 13, 2026
Algebraic Manipulation · difficulty 3 of 5 · about 2 min · position P16-20

Suppose that the number aa satisfies the equation 4=a+a−14 = a + a^{ - 1} . What is the value of a4+a−4a^{4} + a^{ - 4} ?

  1. A)

    164164

  2. B)

    172172

  3. C)

    192192

  4. D)

    194194

  5. E)

    212212

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