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VCE Stuff => VCE Mathematics => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE General & Further Mathematics => Topic started by: dfgjgddjidfg on November 04, 2012, 05:42:58 pm

Title: vcaa 2010 graphs and relations
Post by: dfgjgddjidfg on November 04, 2012, 05:42:58 pm
She sells two Snorestop pillows for each Softsleep pillow sold. so if z=snorestop pillows sold and x=softsleep
shouldnt 2z=x rather than z=2x
Title: Re: vcaa 2010 graphs and relations
Post by: Nima2703 on November 04, 2012, 06:51:54 pm
In further we can only have 2 variables so youre meant to add it on because x+y+2x<150 so you just made is 3x+y<150 (<=equal to)
Title: Re: vcaa 2010 graphs and relations
Post by: julie9300 on November 04, 2012, 07:38:25 pm
In further we can only have 2 variables so youre meant to add it on because x+y+2x<150 so you just made is 3x+y<150 (<=equal to)

I think what they mean is that z=2x means the opposite to what the information has said.

I also got stuck at this question and worked out 2z=x as well. If it wasn't for having to prove the equation, I wouldn't have figured that the answer is suppose to be z=2x.
Title: Re: vcaa 2010 graphs and relations
Post by: Daenerys Targaryen on November 04, 2012, 09:16:46 pm
because she sells 2z for every x; we can assume that z=2x.
that probably doesnt make too much sense. let me explain further

if she sells two z for every x
 - for every x there is 2x (if we assume they are both x's now)
thus z=2x

haha i suck at explaining stuff, hope this helps in some sort of way
Title: Re: vcaa 2010 graphs and relations
Post by: plato on November 04, 2012, 09:28:52 pm
Try simplifying with actual values.
Using z=2x
: if x = 1 then z = 2
: if x = 8 then z = 16
In this way, there are 2 lots of z for every one lot of x as asked for

If you use 2z = x
: if x = 4 then z = 2
: if x = 8 then z = 4
In this way, there are 2 lots of x for every one lot of z which is the opposite.