If it is tangent to the +x and +y axes, the center must also lie along the line
x = y, so that it is equidistant from both axes. The two lines cross at
y -2y +2 = 0, where y = 2.
Therefore x = y = 2 at the center. The radius is R = 2, for tangency.
The equation of the circle is
(x-2)^2 + (y-2)^2 = R^2 = 4
what is the equation of the circle whose centre lies on the line x-2y+2=0 and which touches the positive axes.
1 answer