SOLUTION: How do I find equation: x y 4 11 16 86 9 __ __ -26.5 Equation:___________ __

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Question 309208: How do I find equation:
x y
4 11
16 86
9 __
__ -26.5
Equation:______________
Answer by JBarnum(2146) About Me  (Show Source):
You can put this solution on YOUR website!
Im going to guess that ur list is of points that are all on the same line. in this case use the first 2 points to find the slope.
m=%28y-y%29%2F%28x-x%29 (4,11)(16,86)
m=%2886-11%29%2F%2816-4%29
m=%2875%29%2F%2812%29
m=%2825%29%2F%284%29
no we need to find the y intercept
y=mx%2Bb
11=%2825%2F4%294%2Bb
11=%2825%29%2Bb
-14=b
rewrite equation
y=%2825%2F4%29x-14 or 4y-25x=-7%2F2
now to check for the missing points
(9,y)
y=%2825%2F4%299-14
y=56.25-14
y=42.25or 169%2F4
(x,-26.5)
4y%2B7%2F2=-25x
4%28-26.5%29%2B7%2F2=-25x
-106%2B7%2F2=-25x
-219%2F2=-25x
-219=-50x
219%2F50=x
4.38=x