SOLUTION: WRITE THE EQUATION OF THE LINE PASSING THROUGH (-2,-6)AND(4,-6)

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Question 121054: WRITE THE EQUATION OF THE LINE PASSING THROUGH (-2,-6)AND(4,-6)
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
First lets find the slope through the points (-2,-6) and (4,-6)

m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29 Start with the slope formula (note: is the first point (-2,-6) and is the second point (4,-6))

m=%28-6--6%29%2F%284--2%29 Plug in y%5B2%5D=-6,y%5B1%5D=-6,x%5B2%5D=4,x%5B1%5D=-2 (these are the coordinates of given points)

m=+0%2F6 Subtract the terms in the numerator -6--6 to get 0. Subtract the terms in the denominator 4--2 to get 6


m=0 Reduce

So the slope is
m=0

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Now let's use the point-slope formula to find the equation of the line:



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

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

y--6=%280%29%28x--2%29 Plug in m=0, x%5B1%5D=-2, and y%5B1%5D=-6 (these values are given)


y%2B6=%280%29%28x--2%29 Rewrite y--6 as y%2B6


y%2B6=%280%29%28x%2B2%29 Rewrite x--2 as x%2B2


y%2B6=0x%2B%280%29%282%29 Distribute 0

y%2B6=0x%2B0 Multiply 0 and 2 to get 0

y=0x%2B0-6 Subtract 6 from both sides to isolate y

y=0x-6 Combine like terms 0 and -6 to get -6

y=-6 Remove the zero term
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Answer:


So the equation of the line which goes through the points (-2,-6) and (4,-6) is:y=-6

The equation is now in y=mx%2Bb form (which is slope-intercept form) where the slope is m=0 and the y-intercept is b=-6

Notice if we graph the equation y=-6 and plot the points (-2,-6) and (4,-6), we get this: (note: if you need help with graphing, check out this solver)

Graph of y=-6 through the points (-2,-6) and (4,-6)

Notice how the two points lie on the line. This graphically verifies our answer.