Answer
$x=12^\circ$
The two angles are:
$11\times 12^\circ-20^\circ=112^\circ$
$7\times12^\circ+28^\circ=112^\circ$
Work Step by Step
The two given angles form a straight angle, which means that they are equal.
$7x+28^\circ=11x-20^\circ$
$48^\circ=4x$
$x=12^\circ$
The two angles are:
$11\times 12^\circ-20^\circ=112^\circ$
$7\times12^\circ+28^\circ=112^\circ$