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What is the equation of the line

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What is the equation of the line through x-intercept,-1, and y-intercept ,2?
 
The x-intercept is the point (-1,0) and the y-intercept is the point (0,2).
 
The equation of a line is:
 
y = mx + b
 
Where m = the slope of the line and b is the y-intercept.  We already know the y-intercept, b=2. So all we need is the slope, m.  The slope is defined as the change in y over the change in x between any two points (x1,y1) and (x2,y2) on the line:
 
         (y2 - y1)
m =  ------------
         (x2 - x1)
 
We have two points: the x-intercept (-1,0) and the y-intercept (0,2).  Hence:
 
 
        (y2 - y1)       (2 - 0)        2
m =  ---------- =   --------   =  ---  = 2
        (x2 - x1)     (0 - (-1))      1
 
Therefore the equation of the line is:
 
y = 2x + 2