Questions about the world of GMAT Math from other sources and general math related questions.
knyc
 
 

-1 w/ fractions

by knyc Thu Feb 21, 2008 9:57 pm

Can anyone please explain why:
3 - x/x - 3 = -1
blue_lotus
 
 

by blue_lotus Fri Feb 22, 2008 7:09 am

L.H.S = (3-x)/(x-3)
Note 3 - x = -(-3 + x)
= -( x - 3) [ in addition and substraction you can always swap the numbers as long as they carry the sign associated with them ]

Therefore L.H.S = -(x-3)/(x-3)
= -1 ( for all x not equal to 3 )
knyc
 
 

Thank you!

by knyc Fri Feb 22, 2008 1:49 pm

thank you so much. really helped!