Monday
May 20, 2013

# Homework Help: 8th Grade Math

Posted by Sarah on Thursday, September 24, 2009 at 7:49pm.

If x/y=4, x-y=9, and y-x=-9, what is x & y?

• 8th Grade Math - MathMate, Thursday, September 24, 2009 at 9:08pm

x/y=4, means x=4y
substitute 4y for x in x-y=9
to get
(4y)-y = 9

Can you continue?

Note: the third equation (y-x)=-9 can be derived from the second (x-y)=9, so it gives no new information.

• 8th Grade Math - yves, Monday, January 3, 2011 at 7:06pm

3y

Related Questions

8th grade - im in advanced math so i do 8th grade math and i dont understand how...
8th Grade - Me and my friend are making our own 8th grade binder, you know like...
what can i compare middle school to? - what can i compare middle school to? (use...
8th Grade - Whta is a verctorican (srry i can't spell that) award when the ...
7th grade - Okay, so what are the axiom names? (honors math) Should this go in ...
english - - Computers - English - Foreign Languages - Health - Home Economics - ...
math - what is the difference between translation , rotation, relections, and ...
fractions - Mr.shafier has been teaching school for 10 years.For 6 of those ...
8th Grade Math - If x/y=4, x-y=9, and y-x=(-9) then what is x and y?