Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1exp 11/4/83; site ihuxf.UUCP Path: utzoo!linus!security!genrad!grkermit!masscomp!clyde!ihnp4!ihuxf!rwhaas From: rwhaas@ihuxf.UUCP (Roy W. Haas) Newsgroups: net.math Subject: Re: UCSB competition problem Message-ID: <1633@ihuxf.UUCP> Date: Wed, 16-Nov-83 10:06:42 EST Article-I.D.: ihuxf.1633 Posted: Wed Nov 16 10:06:42 1983 Date-Received: Thu, 17-Nov-83 06:14:51 EST References: <345@sun.UUCP> Organization: AT&T Bell Labs, Naperville, Il Lines: 22 Recall: x^2 = 1 + (y-z)^2 y^2 = 2 + (z-x)^2 z^2 = 3 + (x-y)^2 Actually, no trig is necessary to solve this system. The "trick" if there is one, is to realize that any pair of the equations yield a pair of linear equations. For example, the first two may be used to solve for x and y in terms of z, and then the value of z is found from the third equation. There are two solutions, namely (x,y,z)= +-(5,8,9)/sqrt(24) the second solution comes from the obvious fact that all the signs may be changed. The identity a^2-b^2 = (a+b)(a-b) is handy in solving a given pair. Roy Haas ihuxf!rwhaas