circumcircle in a quadrilateral [closed]

ABCD is a convex quadrilateral with AC and BD intersecting at E. F is a point on AD such that EF is parallel to CD. It is given that the circumcircle of triangle AED is tangential to DC. If FD=336 and FA=420, what is ED?

#Geometry

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Do not post this week's problems expecting someone to answer them. Work on them yourself. You can review the solution next week.

Calvin Lin Staff - 8 years, 4 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$