Since Angle P and Angle M are supplementary angles, two angles are supplementary if the sum of their measures is equaled 180 degrees. Thus, we make this equation,
[tex]\angle P\text{ + }\angle M=180^{\circ}[/tex]Substituting the proportional relationship of Angle P to Angle M,
[tex]\angle P\text{ + }\angle M=180^{\circ}\text{ ; (2}\angle M\text{ + 3) + }\angle M=180^{\circ}[/tex][tex]3\angle M=180-3=177^{\circ}[/tex][tex]\angle M\text{ = }\frac{177^{\circ}}{3}=59^{\circ}[/tex]Since we now have the measure of Angle M, let's now find the measure of Angle P,
[tex]\angle P\text{ + }\angle M=180^{\circ}[/tex][tex]\angle P+59^{\circ}=180^{\circ}[/tex][tex]\angle P=180^{\circ}-59^{\circ}=121^{\circ}[/tex]