Question 68883
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Slope is given by the formula:

      Rise     Change in y       y<sub>2</sub> - y<sub>1</sub>      
m =  _____  =  ___________   =   ________
    
      Run      Change in x       x<sub>2</sub> - x<sub>1</sub>  
     

Let ( 1, -3) = (x<sub>1</sub>, y<sub>1</sub>)
    (-2, -3) = (x<sub>2</sub>, y<sub>2</sub>)

Substitute the values to the formula of the slope

     -3 - (-3)       0
m = __________   =  ___  =  0 ; The graph is a horizontal line

     -2 -  1        -3
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