SOLUTION: Let C be a circle with center O and radius r. Let P be a point such that OP = d > r. Find the length of the tangent line from P to C? HELP!
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-> SOLUTION: Let C be a circle with center O and radius r. Let P be a point such that OP = d > r. Find the length of the tangent line from P to C? HELP!
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Question 431186: Let C be a circle with center O and radius r. Let P be a point such that OP = d > r. Find the length of the tangent line from P to C? HELP! Answer by Edwin McCravy(20056) (Show Source):
A tangent to a circle makes a right angle with the
radius drawn to the point of tangency. So the triangle
drawn is a right triangle and the hypotenuse is d.
We want to find x.
Use the Pythagorean theorem:
r² + x² = d²
x² = d² - r²
_______
x = √d² - r²
Edwin
