
Algebra PreAlgebra and Basic Algebra Math Forum 
 LinkBack  Thread Tools  Display Modes 
April 30th, 2015, 10:00 AM  #1 
Member Joined: Feb 2014 Posts: 91 Thanks: 1  Where did this exponent come from? Not sure about this, please assist. 
April 30th, 2015, 10:37 AM  #2 
Math Team Joined: Jul 2011 From: Texas Posts: 2,924 Thanks: 1521 
you were given ... $y^2=5x^2$ $y = x1$ substitute $(x1)$ for $y$ in the first equation ... $(x1)^2 = 5x^2$ 
April 30th, 2015, 10:39 AM  #3 
Math Team Joined: Jan 2015 From: Alabama Posts: 3,264 Thanks: 902 
You are given the two equations $\displaystyle x^2+ y^2= 5$ and $\displaystyle x y= 1$. Subtrating $\displaystyle x^2$ from both sides of the first equation, $\displaystyle y^2= 5 x^2$ Adding y to both sides of the second equation, $\displaystyle x= 1+ y$. Subtracting 1 from both sides of that equation, $\displaystyle x 1= y$ So we can replace y by x 1 in $\displaystyle y^2= 5 x^2$: $\displaystyle (x 1)^2= 5 x^2$. Essentially then the exponent, 2, in that equation come form the exponent on y in the equation $\displaystyle x^2+ y^2= 5$. 
May 1st, 2015, 07:21 PM  #4 
Senior Member Joined: Nov 2010 From: Indonesia Posts: 2,001 Thanks: 132 Math Focus: Trigonometry 
If you are that confused, just write y = y between the second and the third line, hope you understand.


Tags 
exponent 
Thread Tools  
Display Modes  

Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
Exponent  bml1105  Algebra  12  July 27th, 2014 11:40 AM 
Exponent  Thinkhigh  Calculus  3  March 2nd, 2012 06:42 AM 
Exponent Question  duncanrager  Algebra  5  March 12th, 2011 05:23 PM 
Exponent Questions  xnarutox  Algebra  3  October 27th, 2010 06:49 PM 
Exponent/powers  nicolodn  Elementary Math  1  October 10th, 2010 01:54 AM 