To find an equation for the two adjacent angles described in your illustration, we need to understand the relationship between them.
The angle between the first ray (to the left) and the third ray (to the top right) is given as \( (2x + 3)^\circ \), and the angle between the second ray (to the right) and the third ray is given as \( (x - 6)^\circ \).
Since these two angles are adjacent and form a straight line with the third ray, their sum must equal \( 180^\circ \):
\[ (2x + 3) + (x - 6) = 180 \]
This is the equation that represents the relationship between the two adjacent angles.