The value of the $\measuredangle IEP$ in the figure below

geometry

In a right triangle ABC straight at B, $\measuredangle C = 37^\circ. $If $E$ is an excenter in relation to BC, I is an incenter and $P$ is the point of tangency of the circle inscribed with AC.
calculate $\measuredangle IEP$

My progres::
I made the drawing and marked the relationships found

Let $KE \perp CB$

AE is angle bissector = $\frac{53}{2} \implies \measuredangle AEJ = \frac{137}{2}\\
JEK =90^\circ\implies \measuredangle KEI = \frac{53}{2}$

but I still haven't found the link to find $\angle IEP$

enter image description here

Best Answer

Given $\triangle ABC$ is right triangle, you can easily show that

$BC = R + r$, where $R$ and $r$ are respectively the radii of the excircle on side $BC$ and the incircle.

So, $CP = R$.

Now $\triangle AEH$ is a special triangle with ratio of sides $EH:AH = 1:2$

$\implies R: (R + r + AP) = 1: 2$

$R = r + AP = AB = EH$

Also, $BC = PH = R + r$

So $\triangle ABC \sim \triangle EHP$

$\angle EPH = 37^\circ$

$\therefore \angle IEP = 37^\circ - \frac{53^\circ}{2} = 10.5^\circ$