



 
Hi Kiera, The equation of a circle with radius r and centre (h, k) is (x  h)^{2} + (y  k)^{2} = r^{2}. A tangent to a circle at a point on the circle is perpendicular to the radius at the same point. What is the perpendicular distance from the centre to the Xaxis? What is the radius of the circle? Penny  


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