The equilibrium point in a supply-demand system is where both supply and demand intersect. At the intersection point, x and p will be the same for both supply and demand.
We then can solve this as a system of equations. As we have both equation expressed in function of p, we can write:

Now that we know that x = 80 in the intersection point, we can calculate p using any of the two equations (NOTE: they should give the same result) as:

Answer: the equilibrium point is (x,p) = (80, 122)