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Equation for undefined slope


Date: 10/24/1999 at 18:43:21
From: Andy
Subject: Equation for undefined slope

How do you write an equation for a vertical line with an undefined 
slope?

     Example: vertical line with an x-intercept of 8

Thank you for your time.

Sincerely,
Andy


Date: 10/24/1999 at 22:49:40
From: Doctor Tom
Subject: Re: Equation for undefined slope

How about

     x = 8

To avoid the problems of lines that have infinite slopes, don't use 
the equation y = mx + b; instead use the equation 

     ax + by + c = 0

All lines (even with infinite slopes) can be represented using that 
equation.

- Doctor Tom, The Math Forum
  http://mathforum.org/dr.math/

Associated Topics:
High School Basic Algebra
High School Linear Equations
Middle School Algebra
Middle School Equations

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