Math Question: One large circle and one small circle touch each other externally.A line emerging from center of large circle becomes tangent and touches small circle.length of tangent is 5 cm.find radii of both circles.

Hi, This is a classic problem, but I think you also need to know the radius of the small circle to find the radius of the big circle. The 5 cm line from the center of the big circle touches the small circle at a right angle to the radius of the small circle. These are two segments of a right triangle. Then if you draw a line from the center of the small circle to the center of the big circle, that is the hypotenuse. You can compute that by squaring the radius of the small circle, add to 25 (5 squared) and then taking the square root of the sum, which turns out to be the distance between the center of both circles..So if you also know the length of the radius of the small circle, you can figure out the length of the big circle by subtracting the radius of the small circle from the hypotenuse which connects the centers of both circles. So I don’t believe this question as stated can be answered mathematically.you need the radius of the small circle. Hope that helps!
Answered On 04/20/2020 20:06