SOLUTION: Write an equation in point-slope form of the line that passes through the given point and has the given slope m: 2. (-11,-3), m = -9 Would you please also work out the problem

Algebra ->  Linear-equations -> SOLUTION: Write an equation in point-slope form of the line that passes through the given point and has the given slope m: 2. (-11,-3), m = -9 Would you please also work out the problem      Log On


   

Question 820877: Write an equation in point-slope form of the line that passes through the given point and has the given slope m:
2. (-11,-3), m = -9
Would you please also work out the problem so i know and understand how to do it in the future?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The form of the general point-slope equation is:
+y+=+m%2Ax+%2B+b+
+m+ = the slope of the line
+b+ = the y-intercept
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The slope is always m = ( change in y ) / ( change in x )
In the following formula, +y+ is ANY +y+
and +x+ is ANY +x+
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given the point (-11,-3) and +m=-9+
----------------------------------
+%28+y+-%28-3%29+%29+%2F+%28+x+-%28-11%29+%29+=+-9+
This is just ( change in y ) / ( change in x ) = m
+%28+y+%2B+3+%29+%2F+%28+x+%2B+11+%29+=+-9+
+y+%2B+3+=+-9%2A%28+x+%2B+11+%29+
+y+%2B+3+=+-9x+-+99+
+y+=+-9x+-+102+
-----------------
This is now in the form +y+=+m%2Ax+%2B+b+
check: does it go through the point ( -11,-3 )?
+-3+=+-9%2A%28-11%29+-+102+
+-3+=+99+-+102+
+-3+=+-3+
OK
Here's a plot of the line:
+graph%28+400%2C+400%2C+-16%2C+6%2C+-120%2C+20%2C+-9x+-+102+%29+