SOLUTION: Please help me solve this equation:(0,8)m=-3

Algebra ->  Linear-equations -> SOLUTION: Please help me solve this equation:(0,8)m=-3       Log On


   



Question 130003: Please help me solve this equation:(0,8)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 (0,8), 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=%28-3%29%28x-0%29 Plug in m=-3, x%5B1%5D=0, and y%5B1%5D=8 (these values are given)


y-8=-3x%2B%28-3%29%28-0%29 Distribute -3

y-8=-3x%2B0 Multiply -3 and -0 to get 0

y=-3x%2B0%2B8 Add 8 to both sides to isolate y

y=-3x%2B8 Combine like terms 0 and 8 to get 8
------------------------------------------------------------------------------------------------------------
Answer:


So the equation of the line with a slope of -3 which goes through the point (0,8) is:

y=-3x%2B8 which is now in y=mx%2Bb form where the slope is m=-3 and the y-intercept is b=8

Notice if we graph the equation y=-3x%2B8 and plot the point (0,8), we get (note: if you need help with graphing, check out this solver)

Graph of y=-3x%2B8 through the point (0,8)
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 (0,8), this verifies our answer.