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Finding the Equation of a Line

Date: 2/2/96 at 16:54:3
From: Anonymous
Subject: Problem

I cannot solve this problem - please can you help me?

Find the value of k and m if the straight line y = kx + m passes 
through the point (-2,5) and has a gradient of 4.

Date: 6/10/96 at 20:38:10
From: Doctor Leigh
Subject: Re: Problem

This problem asks you to find the slope (k) and the y intercept (m) 
of a line that passes through a point (-2,5) and has a slope of 4
(gradient is slope).  So right away we know that k = 4.

Now if we substitute (-2,5) into the equation of a line (y = kx + m) 
we should be able to solve for m.

5 = (4)(-2) + m
5 = -8 + m
13 = m

So your answer is k = 4 and m = 13.

Thank you for your question.

-Doctor Leigh Ann,  The Math Forum

Associated Topics:
Middle School Graphing Equations

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