VTMO 2020 — Grade 9 — vtmo Question 12

$ABC$ is right isosceles at $A , AB = 6 \,\mathrm{cm}$. $M$ on $AB$ has $AM = 4 , N$ on $AC$ has $AN = 2$. $P , Q$ on $BC$ have $PM , QN$ perpendicular $MN$. Find area $MNQP$.