SOLUTION: Question: Find the length of a tangent line segment from (10,5) to the circle {{{ x^2+y^2= 25 }}}

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Question 1188272: Question: Find the length of a tangent line segment from (10,5) to the circle +x%5E2%2By%5E2=+25+
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
Draw this. The distance from the point to the center of the circle (the origin) is sqrt 125.
the radius of the circle is 5.
There is a right triangle formed by the radius and the tangent line, with the hypotenuse's being the distance from the center.
So r^2+ tangent line^2=distance from origin^2
so 25 +tl^2=125
tl=10 units