Thanks!The points A, B and C have Co-ordinates (5,1)(p,7)(8,2) respectively.
Given that AB is twice the distance of AC. Calculate the possible values of p.
$\displaystyle You\ have\ two\ solutions.$
$\displaystyle Calculate\ the\ length\ of\ AC\ using\ Pythagoras'\ theorem.$
$\displaystyle Then\ B\ lies\ on\ a\ circle\ of\ twice\ that\ radius.$
$\displaystyle The\ y\ co-ordinate\ of\ both\ points\ is\ 7.$
$\displaystyle Solve\ for\ the\ two\ values\ of\ x.$