Question 29
Sides $AB,$ $BC,$ $CD,$ and $DA,$ respectively, of convex quadrilateral $ABCD$ are extended past $B,$ $C,$ $D,$ and $A$ to points $B',$ $C',$ $D',$ and $A'.$ Also, $AB=BB'=6,$ $BC=CC'=7,$ $CD=DD'=8,$ and $DA=AA'=9;$ and the area of $ABCD$ is $10.$ The area of $A'B'C'D'$ is