SOLUTION: Please help. Write the equation of the line that passes through point (–1, –8) with a slope of 6. Thanks JMS

Algebra ->  Points-lines-and-rays -> SOLUTION: Please help. Write the equation of the line that passes through point (–1, –8) with a slope of 6. Thanks JMS      Log On


   

Question 116195: Please help.
Write the equation of the line that passes through point (–1, –8) with a slope of 6.
Thanks
JMS
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 6 which goes through the point (-1,-8), 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--8=%286%29%28x--1%29 Plug in m=6, x%5B1%5D=-1, and y%5B1%5D=-8 (these values are given)


y%2B8=%286%29%28x--1%29 Rewrite y--8 as y%2B8


y%2B8=%286%29%28x%2B1%29 Rewrite x--1 as x%2B1


y%2B8=6x%2B%286%29%281%29 Distribute 6

y%2B8=6x%2B6 Multiply 6 and 1 to get 6

y=6x%2B6-8 Subtract 8 from both sides to isolate y

y=6x-2 Combine like terms 6 and -8 to get -2
------------------------------------------------------------------------------------------------------------
Answer:


So the equation of the line with a slope of 6 which goes through the point (-1,-8) is:

y=6x-2 which is now in y=mx%2Bb form where the slope is m=6 and the y-intercept is b=-2

Notice if we graph the equation y=6x-2 and plot the point (-1,-8), we get (note: if you need help with graphing, check out this solver)

Graph of y=6x-2 through the point (-1,-8)
and we can see that the point lies on the line. Since we know the equation has a slope of 6 and goes through the point (-1,-8), this verifies our answer.