Find "d" if the slope of the line containing the two points (3,11) & (-6,d) is 1/3?

Question

That's the question I have, so in problems generally like this one, how do I find d? Step by step would be most helpful and 10 points for best answer :D

Answer 1

given points    (3 ,11)  (-6 , d)

the  slope is 1/3

the formula of the slope  (y2 -y1)/ (x2 - x1)----------1

x1=3 ,y1 =11, x2 = -6 , y2 = d

substute the values equation 1

          (d -11 )/ ( -6 -3) = 1/3

         (d -11) / -9 = 1/3

multipling eachside by -9

          ( d -11 ) = (1/3)* -9

           d -11  = -3   ( (1 /3)*-9 = -3)

add 11 to eachside

           d -11 + 11 = -3 + 11

                       d = 8

the value d = 8

Answer 2

given points    (3 ,11)  (-6 , d)

the  slope is 1/3

the formula of the slope = change in y / change in x =(y2-y1) / (x2 - x1)

x1=3 ,y1 =11, x2 = -6 , y2 = d

substute the values in formula of the slope

          (d -11 )/ ( -6 -3) = 1/3

         (d -11) / -9 = 1/3        (multipling eachside by -9)

          ( d -11 ) = (1/3)* -9

           d -11  = -3                  ( (1 /3)*-9 = -3)

           d -11 + 11 = -3 + 11   (add 11 to eachside)

             d = 8

the value d = 8