SOLUTION: Write the equation of the line with slope 2 and y-intercept (0, –4).

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Question 111292: Write the equation of the line with slope 2 and y-intercept (0, –4).
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 2 which goes through the point (0,-4), 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--4=%282%29%28x-0%29 Plug in m=2, x%5B1%5D=0, and y%5B1%5D=-4 (these values are given)


y%2B4=%282%29%28x-0%29 Rewrite y--4 as y%2B4


y%2B4=2x%2B%282%29%28-0%29 Distribute 2

y%2B4=2x%2B0 Multiply 2 and -0 to get 0

y=2x%2B0-4 Subtract 4 from both sides to isolate y

y=2x-4 Combine like terms 0 and -4 to get -4
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Answer:


So the equation of the line with a slope of 2 which goes through the point (0,-4) is:

y=2x-4 which is now in y=mx%2Bb form where the slope is m=2 and the y-intercept is b=-4

Notice if we graph the equation y=2x-4 and plot the point (0,-4), we get (note: if you need help with graphing, check out this solver)

Graph of y=2x-4 through the point (0,-4)
and we can see that the point lies on the line. Since we know the equation has a slope of 2 and goes through the point (0,-4), this verifies our answer.