SOLUTION: Please help me solve this equation: (-4,3),m=3

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Question 130004: Please help me solve this equation: (-4,3),m=3
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 3 which goes through the point (-4,3), 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=%283%29%28x--4%29 Plug in m=3, x%5B1%5D=-4, and y%5B1%5D=3 (these values are given)


y-3=%283%29%28x%2B4%29 Rewrite x--4 as x%2B4


y-3=3x%2B%283%29%284%29 Distribute 3

y-3=3x%2B12 Multiply 3 and 4 to get 12

y=3x%2B12%2B3 Add 3 to both sides to isolate y

y=3x%2B15 Combine like terms 12 and 3 to get 15
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Answer:


So the equation of the line with a slope of 3 which goes through the point (-4,3) is:

y=3x%2B15 which is now in y=mx%2Bb form where the slope is m=3 and the y-intercept is b=15

Notice if we graph the equation y=3x%2B15 and plot the point (-4,3), we get (note: if you need help with graphing, check out this solver)

Graph of y=3x%2B15 through the point (-4,3)
and we can see that the point lies on the line. Since we know the equation has a slope of 3 and goes through the point (-4,3), this verifies our answer.