Question 7
The midpoints of the sides $AB$, $BC$, $CD$, $DA$ of a convex quadrilateral $ABCD$ lie on the same circle. If $AB=10$ cm, $BC=11$ cm and $CD=12$ cm, determine, in cm, the length of the side $DA$.
Answer-entry note: give an exact value; a square root may be entered as sqrt(...), without units.
Answer-entry note: give an exact value; a square root may be entered as sqrt(...), without units.