
Algebra PreAlgebra and Basic Algebra Math Forum 
 LinkBack  Thread Tools  Display Modes 
June 13th, 2018, 08:08 AM  #1 
Senior Member Joined: Oct 2013 From: New York, USA Posts: 622 Thanks: 85  Solve This Equation For xy
3x^2 + xy = 2y^2 Can you solve for xy? 
June 13th, 2018, 09:37 AM  #2 
Global Moderator Joined: Oct 2008 From: London, Ontario, Canada  The Forest City Posts: 7,884 Thanks: 1088 Math Focus: Elementary mathematics and beyond 
Hi EvanJ. $$3x^2 + xy = 2y^2$$ $$3x^2+xy2y^2=0$$ $$(3x2y)(x+y)=0\implies 3x=2y,x=y$$ $$3x^2=2xy$$ $$xy=y^2$$ Now sub into the original equation and take it from there. 
June 13th, 2018, 10:25 AM  #3 
Math Team Joined: Oct 2011 From: Ottawa Ontario, Canada Posts: 13,600 Thanks: 954 
Using quadratic: solve for x : x = y or x = 2y/3 solve for y : y = x or y = 3x/2 Just trying to cause confusion 
June 13th, 2018, 04:48 PM  #4 
Math Team Joined: Dec 2013 From: Colombia Posts: 7,511 Thanks: 2514 Math Focus: Mainly analysis and algebra  

Tags 
equation, solve 
Thread Tools  
Display Modes  

Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
Solve the equation...  boomer029  Algebra  8  March 17th, 2012 06:09 PM 
Solve Equation  ijkm  Abstract Algebra  1  March 15th, 2012 02:13 AM 
Solve equation  Valar30  Algebra  2  March 11th, 2011 07:47 PM 
How can I solve this equation?  Begtostudy  Linear Algebra  3  July 29th, 2010 07:11 PM 