## Precalculus (6th Edition)

$55^\circ 9'$
In this kind of substraction, we substract the degrees from the degrees and the minutes from the minutes: $180^\circ$ can be rewritten as: $179^\circ 60'$ $179^\circ 60'-124^\circ 51'=(179-124)^\circ+(60-51)'=55^\circ 9'$