SOLUTION: Find an equation of the line containing the given pair of points? (-7,-2)and(-5,-9)

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Question 950813: Find an equation of the line containing the given pair of points? (-7,-2)and(-5,-9)
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
:
Find an equation of the line containing the given pair of points? (-7,-2)and(-5,-9)
Find the slope: m = %28%28y2-y1%29%29%2F%28%28x2-x1%29%29
Assign the given pairs as follows
x1=-7; y1=-2
x2=-5; y2=-9
Find the slope
m = %28%28-9-%28-2%29%29%29%2F%28%28-5-%28-7%29%29%29
minus a minus is a plus
m = %28%28-9%2B2%29%29%2F%28%28-5%2B7%29%29 = %28-7%29%2F2
Use the form y = mx + b, where y=-2 and x=-7 and m = -7%2F2
-2 = -7%2F2(-7) + b
-2 = 49%2F2 + b
lets us the decimal here
-2 = 24.5 + b
-2 - 24.5 = b
-26.5 - = b
b = -26.5
the equation then
y = -7%2F2x - 26.5
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Confirm this for yourself.
substitute the given x's and ensure they equal the given y's