We can say that the two triangles are identical, then, the angle GPK is equal to the angle KPH, then we write the following equation:

Now we know the value of x, we can return to the equation and find the value of the angle GPK
![\begin{gathered} \angle GPK=18x+5 \\ \\ \operatorname{\angle}GPK=18\cdot(5)/(2)+5 \\ \\ \operatorname{\angle}GPK=9\cdot5+5 \\ \\ \operatorname{\angle}GPK=45+5 \\ \\ \angle GPK=50 \end{gathered}]()
Therefore, the measure of the angle GPK is equal to 50 degrees