SOLUTION: Write the equation of the line that passes through the points (2,-4) and (-2,-2):

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Question 979363: Write the equation of the line that passes through the points (2,-4) and (-2,-2):
Found 2 solutions by josgarithmetic, MathTherapy:
Answer by josgarithmetic(39623) About Me  (Show Source):
You can put this solution on YOUR website!
Imagine you had any two points, (p,q) and (u,v), and wanted to find equation of a line that passes through these two points. You could use the formula for slope, and the point-slope form or the slope-intercept form of linear equation.

m=%28v-q%29%2F%28u-p%29

Examining the slope intercept form,
y=mx%2Bb
y-mx=b
b=y-mx
-
pick one of the given points, either that you wish.
b=v-mu--------this line is not rendering correctly. In pure text it is b=v-m*u.
b=v-%28%28v-q%29%2F%28u-p%29%29u
-
highlight%28y=%28%28v-q%29%2F%28u-p%29%29x%2Bv-%28%28v-q%29%2F%28u-p%29%29u%29

You could just plug-in the values for p, q, u, and v, and simplify the equation.

Answer by MathTherapy(10555) About Me  (Show Source):
You can put this solution on YOUR website!

Write the equation of the line that passes through the points (2,-4) and (-2,-2):
STEP 1

Find the slope

%28y%5B1%5D+-+y%5B2%5D%29%2F%28x%5B1%5D+-+x%5B2%5D%29

%28-+4+-+-+2%29%2F%282+-+-+2%29 ------- Substituting (2, - 4) for system%28x%5B1%5D_and%2Cy%5B1%5D%29 and (- 2, - 2) for system%28x%5B2%5D_and%2Cy%5B2%5D%29

%28-+6%29%2F4______-+3%2F2 ------- m (slope)



 

y+-+y%5B1%5D+=+m%28x-+x%5B1%5D%29 ------- Point-slope form

y+-+-+4+=+%28-+3%2F2%29%28x-+2%29 ------- Substituting (2, - 4) for system%28x%5B1%5D_and%2Cy%5B1%5D%29 and -+3%2F2 for slope

y+%2B+4+=+%28-+3%2F2%29x+%2B+3

y+=+%28-+3%2F2%29x+%2B+3+-+4

highlight_green%28y+=+%28-+3%2F2%29x+-+1%29