Problem B. 4726. (September 2015)
B. 4726. In a square \(\displaystyle ABCD\), points \(\displaystyle P\) and \(\displaystyle Q\) lie on sides \(\displaystyle AB\) and \(\displaystyle BC\), respectively, and \(\displaystyle BP = BQ\). Let \(\displaystyle T\) denote the foot of the perpendicular dropped from vertex \(\displaystyle B\) to the line segment \(\displaystyle PC\). Prove that \(\displaystyle \angle DTQ\) is a right angle.
(4 pont)
Deadline expired on 12 October 2015.
Statistics:
165 students sent a solution.  
4 points:  109 students. 
3 points:  32 students. 
2 points:  5 students. 
1 point:  8 students. 
0 point:  8 students. 
Unfair, not evaluated:  2 solutions. 
Unfair, not evaluated:  1 solution. 
