What is the length of AB if AO is 24 and BC is 27, given that AB is tangent to circle O?

To find the length of AB, we can use the property of tangents to a circle. When a line is tangent to a circle, it is perpendicular to the radius at the point of tangency.

In this case, we have a circle with center O, and point A is on the radius AO which measures 24 units. The length of BC is 27 units, and since AB is tangent to the circle, we can apply the Pythagorean theorem.

Let D be the point where the tangent line AB meets the radius at point O. Thus, we have a right triangle AOD, where:

  • AO = 24 (the radius of the circle)
  • AB is the tangent we wish to find
  • OD = BC = 27 (the distance from the center of the circle to point B, which is along the radius when extended)

Using the Pythagorean theorem:

AB2 + AO2 = OD2

Substituting the known lengths:

AB2 + 242 = 272

Calculating these values gives:

AB2 + 576 = 729

Now, isolate AB²:

AB2 = 729 – 576

AB2 = 153

Taking the square root of both sides:

AB = √153

Thus, the length of AB is approximately 12.37 units.

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