2010 AMC 10B Problems/Problem 13

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Problem

What is the sum of all the solutions of $x = \left|2x-|60-2x|\right|$?

$\mathrm{(A)}\ 32 \qquad \mathrm{(B)}\ 60 \qquad \mathrm{(C)}\ 92 \qquad \mathrm{(D)}\ 120 \qquad \mathrm{(E)}\ 124$

Solution

Case 1: $2x-|60-2x|=x$