Does anyone know this?!? (If you know the answer please type it as how i will need to put it into the box)

Anne is twice as old as bill, and bill is 3 years older than christie. the sum of anne s and christie s ages equal 72. find their age difference.?

Plz me i need i will give a brain

Graph the system: f(x)= 3/x-2; f(x)= 1/2x + 2