Precalculus (6th Edition)

$P=137$ or $P=103$
$P_d=\mid P-120\mid$ Here, $P_d=17$, we substitute in the equation: $17=\mid P-120\mid$ We have two possibilities: $17=P-120$ $P=137$ or $17=120-P$ $P=120-17$ $P=103$