Find the radius of the circle

In the figure shown, L is the center of the circle, and PQ is a chord of the circle measuring 30 centimeters. (cm)

What is the length, in centimeters, of PL ?

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The length of PQ is given as 30 cm.
The length of PM is half of PQ, which would be 15 cm.

A right triangle is created with legs of 15 and 8. PL would be the hypotenuse of the triangle.

Pythagorean Theorem
a² + b² = c²   {sum of the squares of the legs is equal to the square of the hypotenuse}
8² + 15² = c²   {substituted given information into the Pythagorean Theorem}
64 + 225 = c²   {evaluated exponents}
289 = c²   {added 64 and 225}
c = 17   {took square root of each side}

PL = 17 cm

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