# John's strange quadrilateral

Geometry Level 3

Convex quadrilateral $$ABCD$$ has sides $$AB = BC = 21$$, $$CD = 15$$ and $$AD = 9$$. Given additionally that $$\angle ABC = 60^\circ$$, what is the length of $$BD$$?

This problem is proposed by John.

×

Problem Loading...

Note Loading...

Set Loading...