SOLUTION: write the equation in slope intercept form. (-1,2) (1,-4), and (0,0) (-3,-2)

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Question 585857: write the equation in slope intercept form. (-1,2) (1,-4), and (0,0) (-3,-2)
Found 2 solutions by jim_thompson5910, josmiceli:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
I'll do the first one to get you started.



First let's find the slope of the line through the points and


Note: is the first point . So this means that x%5B1%5D=-1 and y%5B1%5D=2.
Also, is the second point . So this means that x%5B2%5D=1 and y%5B2%5D=-4.


m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29 Start with the slope formula.


m=%28-4-2%29%2F%281--1%29 Plug in y%5B2%5D=-4, y%5B1%5D=2, x%5B2%5D=1, and x%5B1%5D=-1


m=%28-6%29%2F%281--1%29 Subtract 2 from -4 to get -6


m=%28-6%29%2F%282%29 Subtract -1 from 1 to get 2


m=-3 Reduce


So the slope of the line that goes through the points and is m=-3


Now let's use the point slope formula:


y-y%5B1%5D=m%28x-x%5B1%5D%29 Start with the point slope formula


y-2=-3%28x--1%29 Plug in m=-3, x%5B1%5D=-1, and y%5B1%5D=2


y-2=-3%28x%2B1%29 Rewrite x--1 as x%2B1


y-2=-3x%2B-3%281%29 Distribute


y-2=-3x-3 Multiply


y=-3x-3%2B2 Add 2 to both sides.


y=-3x-1 Combine like terms.


So the equation that goes through the points and is y=-3x-1


Notice how the graph of y=-3x-1 goes through the points and . So this visually verifies our answer.
Graph of y=-3x-1 through the points and
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Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!

+%28+y+%2B+2+%29+%2F+%28+x+%2B+3+%29+=+2%2F3+
+3%2A%28+y+%2B+2+%29+=+2%2A%28+x+%2B+3+%29+
+3y+%2B+6+=+2x+%2B+6+
+3y+=+2x+
+y+=+%282%2F3%29%2Ax+
here's the plot:
+graph%28+400%2C+400%2C+-5%2C+5%2C+-5%2C+5%2C+%282%2F3%29%2Ax+%29+