SOLUTION: Tangents TK and TL are drawn to a circle of diameter 78. If the distance between T and the centre of the circle is 89, what is the length of TK?

Algebra ->  Circles -> SOLUTION: Tangents TK and TL are drawn to a circle of diameter 78. If the distance between T and the centre of the circle is 89, what is the length of TK?      Log On


   

Question 1190323: Tangents TK and TL are drawn to a circle of diameter 78. If the distance between T and the centre of the circle is 89, what is the length of TK?
Answer by ikleyn(53751) About Me  (Show Source):
You can put this solution on YOUR website!
.

If O is the center of the circle, them OTK is a right angle triangle.


THEREFORE,  TK = sqrt%28TO%5E2-OK%5E2%29 = sqrt%2889%5E2-39%5E2%29 = sqrt%286400%29 = 80  units.    ANSWER


Notice that 39 = 78/2 is the radius of the circle.

Solved.

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If you want to learn more about tangent lines to circles,  look into the lessons
    - A tangent line to a circle is perpendicular to the radius drawn to the tangent point,
    - Tangent segments to a circle from a point outside the circle,
in this site.