Step 1 :Translate the problem into a mathematical equation using the fact that the sum of the angles in a triangle is always 180 degrees. The equation is \((9x + 2) + (x + 15) + (4x - 5) = 180\).
Step 2 :Solve the equation for x. The solution is \(x = 12\).
Step 3 :Substitute the value of x into the expression for m∠P to find the measure of angle P. The measure of angle P is \(4*12 - 5 = 43\) degrees.
Step 4 :The final answer is \(\boxed{43}\) degrees.