47th Putnam 1986

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Problem B1

ABCD is a rectangle. AEB is isosceles with E on the opposite side of AB to C and D and lies on the circle through A, B, C, D. This circle has radius 1. For what values of |AD| do the rectangle and triangle have the same area?

 

Solution

Answer: 2/5.

Trivial.

The height of E above AB is 1 - AD/2. Hence (1 - AD/2) = 2 AD.

 


 

47th Putnam 1986

© John Scholes
jscholes@kalva.demon.co.uk
30 Sep 1999