Question 4
In the trapezium $ABCD$, $AB$ is parallel to $CD$. $E$ and $F$ are points on $AD$ and $BC$ respectively such that $EF$ is also parallel to $AB$. The area, in cm$^2$, of triangles $BAF$, $CDF$ and $BCE$ are 8, 7 and 18 respectively. What is the area, in cm$^2$, of $ABCD$?
