2y = kx + h
2(6) = - 3k + h ---- Substituting (- 3, 6) for (x, y)
12 = - 3k + h ------ eq (i)

2y = kx + h
2(11) = k + h --- Substituting (1, 11) for (x, y)
22 = k + h ------ eq (ii)
10 = 4k --------- Subtracting eq (i) from eq (ii)
 

 ----- Substituting  for k in eq (ii)

1)    is the slope, and it can be easily calculated via the coordinates of the given points


         =  = ;  so   k = .


    You DO NOT NEED to solve system of equation to find k.


2)  As soon as you know "k", substitute it and the coordinates of any of the two point into the given equation to find "h"


        2*11 =  + h,

        h = 22 - 2.5 = 19.5.