What's the measure of the $\angle ACB$?

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For reference: (Exact copy of the problem) In the right triangle, right angle in $B$; $I$ is incenter and $E$ is excenter for $BC$.If $AI = IE$, calculate $\angle ACB$ (answer:$53^o$)

My progress: Drawing according to the statement and placing the relationships we arrive at... (The dots in blue are just to make it easier to see the size of the sides) enter image description here

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$ \small \triangle ABE \sim \triangle AIC$
So, $ \small BE:AB = CI:AI$

But $ \small CI = CE = \frac{IE}{\sqrt2} = \frac{AI}{ \sqrt2}$.

$ \implies \small BE = \frac{AB}{\sqrt2} \tag1$

Also, $ \small \triangle AIB \sim \triangle ACE$,
So, $ \small BI:AB = CE:AE$
But $ \small AE = 2 AI$ and hence $ \small CE:AE = 1: 2 \sqrt2$.

$ \small \implies BI = \frac{AB}{2 \sqrt2} \tag2$

From $(1)$ and $(2)$, $ \small BE = 2 BI $

$ \small \triangle IBE$ is a special right triangle with perp sides in ratio $1:2$.

So we have, $ \small \angle IEB = \frac{\angle C}{2} = 26.5^\circ$

$\therefore \small \angle ACB = 53^\circ$

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From $I$ and $E$ drop perpendiculars to $AC$. These perpendiculars will be inradius $r$ and exradius, $r_a$ respectively.

Since $AI=AE/2$, $r=r_a/2$ using similar triangles.

Using formulas for $r=\Delta / s$ and $r_a = \Delta / (s-a)$, we can obtain

$$b+c=3a$$

Combining this with $b^2-c^2=a^2$, we get $$\frac{c}{b}=\frac{4}{5} \Rightarrow \angle C = \sin^{-1}\frac{4}{5} \approx 53^\circ$$