(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Let AD be and altitude of triangle ABC where angle A is 90 degrees.

Squares BCX1X2, CAY1Y2 and ABZ1Z2 are drawn outwards from the sides.

Let AX1 meet BY2 in U and AAX2 meet CZ1 in V

Prove that each of the quadrilaterals ABDU, ACDV and BX1UV is cyclic

2. Relevant equations

3. The attempt at a solution

I'm not sure where to start, but I've been given a clue

If angle BUA = angle BDA, the ABDU is cyclic

Let the point where BY2 meets AC be P

Consider triangles AUP and Y2CP

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# Homework Help: Geometry problem help

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