SOLUTION: please answer my question: write the equation of a line that passes through (-5,-3)and (7,-3) in slope-intercept form...please answer my question,thankyou

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Question 176421: please answer my question: write the equation of a line that passes through (-5,-3)and (7,-3) in slope-intercept form...please answer my question,thankyou
Found 2 solutions by jim_thompson5910, Alan3354:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

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


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


m=%28-3--3%29%2F%287--5%29 Plug in y%5B2%5D=-3, y%5B1%5D=-3, x%5B2%5D=7, and x%5B1%5D=-5


m=%280%29%2F%287--5%29 Subtract -3 from -3 to get 0


m=%280%29%2F%2812%29 Subtract -5 from 7 to get 12


m=0 Reduce


So the slope of the line that goes through the points and is m=0


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--3=0%28x--5%29 Plug in m=0, x%5B1%5D=-5, and y%5B1%5D=-3


y--3=0%28x%2B5%29 Rewrite x--5 as x%2B5


y%2B3=0%28x%2B5%29 Rewrite y--3 as y%2B3


y%2B3=0x%2B0%285%29 Distribute


y%2B3=0x%2B0 Multiply


y=0x%2B0-3 Subtract 3 from both sides.


y=0x-3 Combine like terms.


y=-3 Simplify


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


Notice how the graph of y=-3 goes through the points and . So this visually verifies our answer.
Graph of y=-3 through the points and

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
I just did one similar to that.
Write the equation of the line that passes through (4,-5) and (7,-3). Express in general form
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The hard way:
find the slope, m, = (diff in y)/(diff in x)
m = (-3 -(-5))/(7-4)
m = 2/3
Use either point:
y-y1 = m*(x-x1)
y+5 = (2/3)*(x-4)
3y+15 = 2x-8
2x-3y = 23
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Better way:
|x y 1|
|4 -5 1| = 0
|7 -3 1|
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x*(-5+3) - y*(4-7) + (-12+35) = 0
-2x + 3y + 23 = 0
2x - 3y = 23