To do this, you need to work out the radius and the centre of each circle ... or the difference between their radii. Two circles will intersect at two points when \({r_1} ...

To find the equation of a circle when you know the radius and centre, use the formula \({(x - a)^2} + {(y - b)^2} = {r^2}\), where \((a,b)\) represents the centre of the circle, and \(r\) is the ...