The slope-intercept form:

m - slope
b - y-intercept → (0, b)
We have the points (-9, -9) and (0, 1) - y-intercept → b = 1.
Calculate the slope:

Answer: 
As this is already in its simplest form, I believe the only other expression is 4*X +9
Answer:
1/28
Step-by-step explanation:
The answer is: " -5/3 " ; or, write as: " -1 ⅔ " .
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Explanation:
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(-5/6) + (-5/6) = (-5/6) <span>− (5/6) ;
------> {since: "adding a negative" is the same a "subtracting a positive"} ;
------> </span> (-5/6) − (5/6) = (-5 − 5) / 6 ;
= -10/6 = (-10/2) / (6/2) ;
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= " -5/3 " ; or, write as: " -1 ⅔ " .
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