Help proving a trianlge is isosceles

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To prove triangle A'EF is isosceles, it is essential to demonstrate that segments A'E and A'F are equal in length or that angles A'EF and A'FE are congruent. A helpful approach involves drawing a circle with diameter BC, which reveals that right angles are inscribed in a semicircle. The next step is to show that segment A'F is congruent to segment A'C by constructing a perpendicular line A'G from A' to CF. Similarly, proving that segment A'E is congruent to segment A'C will complete the proof of the isosceles triangle. This method effectively utilizes geometric properties to establish the necessary congruences.
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Hi. I'm seriously stuck on this problem. I don't even know where to begin.

Homework Statement


Suppose triangle ABC is an acute angle triangle. Let the bases of the altitudes to B and C be E and F, respectively, and let A' be the midpoint of BC. Prove that triangle A'EF is isosceles.

Homework Equations


The Attempt at a Solution


I know that I have to show that A'E and A'F are the same length or that angles A'EF and A'FE are congruent in order to prove the triangle is isosceles. I'm clueless though.There's a typo in the topic title. Sorry.
 
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Hint: Draw the circle with diameter BC and observe the right angles are inscribed in a semicircle.
 
First, show that A'F congruent to A'C. (Try drawing A'G such that G lies on CF and A'G is perpendicular to CF)

Use the same process to show that A'E congruent to A'C
 
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