Just a really quick one, suppose I have a line of equation: y=1/2x+5/2

The next part of the question asks for this in the form of ax+by+c=0

How do I convert from y=mx+c to ax+by+c=0?

Thank youuu! :)

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- Nov 13th 2007, 10:23 AMhymnseekerCoordinate geometry question
Just a really quick one, suppose I have a line of equation: y=1/2x+5/2

The next part of the question asks for this in the form of ax+by+c=0

How do I convert from y=mx+c to ax+by+c=0?

Thank youuu! :) - Nov 13th 2007, 10:24 AMJhevon
- Nov 13th 2007, 10:26 AMhymnseeker
Thanks for the reply, so just let y=0?

1/2x+5/2=0

Does this satisfy what the question wants in asking for ax+by+c=0? - Nov 13th 2007, 10:29 AMJhevon
did you read what i said? i said bring everything over to one side, how does that translate to equating y to zero?

$\displaystyle y = \frac 12x + \frac 52$ ............subtract y from both sides

$\displaystyle \Rightarrow 0 = \frac 12x - y + \frac 52$ ...............multiply through by 2

$\displaystyle \Rightarrow 0 = x - 2y + 5$

which is the same thing as

$\displaystyle x - 2y + 5 = 0$

here a = 1, b = -2 and c = 5 - Nov 13th 2007, 10:35 AMhymnseeker
Thank you for your help. Needed to see it visually - and in answer to your question (although I suspect it was rhetorical), yes, I did read what you said first off.

- Nov 13th 2007, 11:03 AMJhevon