Question 90926

 Write the equation of the line passing through each of the given pairs of points. Write your result in slope-intercept form. A) (-1, 3) and (4, -2); B) (2, -3) and (2, 4). 


   A) (-1,3)(4,-2)

        The formula for finding the equation given two points is 

          y2-y1/y-y1 = x2-x1/x-x1

          -2-3/y-3 = 4-(-1)/x-(-1)

           -5/y-3 = 4+1/x+1

           -5/y-3 = 5/x+1 

        y-3 = -1(x+1)

         y-3 = -x-1
           y = -x-1+3   The required eq'n is y = -x+2


   B)(2,-3)  (2,4)


          The same eq'n is applied

            y2-y1/y-y1 = x2-x1/x-x1 

            4-(-3)/y-(-3) = 2-2/x-2

             4+3/y+3 = 0/x-2

              7/y+3 = 0   since R.H.S   is 0   eq'n is 0