if someone could please show me the steps to finding this, i would really appreciate it. thanx

1) A quadratic relation is given by y=ax^2+b

if the two points P(1,5) and Q(2,11) are on the graph of the relation, then find a and b.

2) A parabola is defined by the equation y=a(x-2)^2+k. the points (0,17) and (2,5) are on the curve. find the equation of the parabola.