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#1 2006-02-13 19:58:23

Titus
Member
Registered: 2005-03-07
Posts: 10

Perpendicular Lines

From the equation 3y = 5 - x

how do you find the gradient? and what is it?

thanks

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#2 2006-02-13 20:19:37

kempos
Member
Registered: 2006-01-07
Posts: 77

Re: Perpendicular Lines

y = (5 - x)/3

gradient = -1/3

equation of a straight line: y = ax + b where a is a gradient.

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#3 2006-02-14 16:19:55

John E. Franklin
Member
Registered: 2005-08-29
Posts: 3,588

Re: Perpendicular Lines

If you are looking for the slant of the line perpendicular to this line, then it is negative one over slope of this line.
The slant of a line is the same anywhere on the line.
This is not true for a more complicated curve.  So the slope of the perpendicular line to this one is
three.


igloo myrtilles fourmis

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#4 2006-02-16 10:42:10

rp_
Member
Registered: 2006-02-10
Posts: 7

Re: Perpendicular Lines

ie. Sometimes its easier to understand when you see the formula

if the line gradient is ½ the the gradient of a perpendicular line will be -(1/(½) = -2

therefore in general the line with gradient m will have a pependicular line with gradient -1/m.

Last edited by rp_ (2006-02-16 10:42:29)

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