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## #1 2006-02-26 13:56:36

x1000uf
Member
Registered: 2006-02-26
Posts: 1

### help me!! y-y1=m(x-x1)

i dont know how to do it with factions someone help??!!!!

im gonna fail becuase i dont know how to do it

y-9=2/5(x+20

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## #2 2006-02-26 19:18:08

MathsIsFun
Registered: 2005-01-21
Posts: 7,685

### Re: help me!! y-y1=m(x-x1)

What was the actual question? How to simplify y-9=2/5(x+20 ) ?

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

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## #3 2006-02-26 19:24:56

ganesh
Registered: 2005-06-28
Posts: 25,035

### Re: help me!! y-y1=m(x-x1)

I guess the question is finding the equation of a straight line whose slope is 2/5 and which passes through the point (-20, 9).

The equation of a straight line passing through a given point (x1, y1) and with a given slope, m, is

y - y1 = m(x - x1).

In the given problem, x1 = -20, y1=9 and m=2/5.
Therefore, the equation of the straight line is

y-9 = 2/5[(x+20)]
5y-45 = 2x + 40
5y - 2x = 85
2x - 5y + 85 = 0 is the required equation.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #4 2006-02-26 21:07:14

krassi_holmz
Real Member
Registered: 2005-12-02
Posts: 1,905

### Re: help me!! y-y1=m(x-x1)

or y=(2x+85)/5?

IPBLE:  Increasing Performance By Lowering Expectations.

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