SOLUTION: Write the equation of the line that passes through point (–1, –3) with a slope of –5.

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Question 92957: Write the equation of the line that passes through point (–1, –3) with a slope of –5.
Found 2 solutions by jim_thompson5910, Tunde:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

If you want to find the equation of line with a given a slope of -5 which goes through the point (-1,-3), you can simply use the point-slope formula to find the equation:


---Point-Slope Formula---
y-y%5B1%5D=m%28x-x%5B1%5D%29 where m is the slope, and is the given point

So lets use the Point-Slope Formula to find the equation of the line

y--3=%28-5%29%28x--1%29 Plug in m=-5, x%5B1%5D=-1, and y%5B1%5D=-3 (these values are given)


y%2B3=%28-5%29%28x--1%29 Rewrite y--3 as y%2B3


y%2B3=%28-5%29%28x%2B1%29 Rewrite x--1 as x%2B1


y%2B3=-5x%2B%28-5%29%281%29 Distribute -5

y%2B3=-5x-5 Multiply -5 and 1 to get -5

y=-5x-5-3 Subtract 3 from both sides to isolate y

y=-5x-8 Combine like terms -5 and -3 to get -8
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Answer:


So the equation of the line with a slope of -5 which goes through the point (-1,-3) is:

y=-5x-8 which is now in y=mx%2Bb form where the slope is m=-5 and the y-intercept is b=-8

Notice if we graph the equation y=-5x-8 and plot the point (-1,-3), we get (note: if you need help with graphing, check out this solver)

Graph of y=-5x-8 through the point (-1,-3)
and we can see that the point lies on the line. Since we know the equation has a slope of -5 and goes through the point (-1,-3), this verifies our answer.

Answer by Tunde(2) About Me  (Show Source):
You can put this solution on YOUR website!
y=mx+c,where m=slope=-5,y=-3, x=-1,&c=interception,sub this values,-3=-5(-1)+c,-3=6+c,-3-6=c. c=-9.