Question 148
Let point $H$ be the orthocenter of a scalene triangle $ABC$. Line $AH$ intersects with the circumcircle $\Omega$ of triangle $ABC$ again at point $P$. Line $BH, CH$ meets with $AC, AB$ at point $E$ and $F$, respectively. Let $PE, PF$ meet $\Omega$ again at point $Q, R$, respectively. Point $Y$ lies on $\Omega$ so that lines $AY, QR, EF$ are concurrent. Prove that $PY$ bisects $EF$.