Slope intercept form is y=mx+b so use your numbers to fill in the blanks
heres an example:
There is no given data table but based on the question, the reaction is
xy <=> x + y
If we let M as the initial concentration of xy and c as the in the concentration after the dissociation, then we can use the ICE method
xy <=> x + y
I M
C -c c c
-----------------------------
E M-c c c
Solve for c using
Kc = c(c) / (M - c)
And the concentration of the xy, x, and y can then be determined