Circle Theorem: Tangents from the Same Point Are the Same Length

Circle Theorem: Tangents from the Same Point Are the Same Length

Two tangents drawn from the same point outside of the circle are the same length and form two congruent right triangles.

How to Use the Circle Theorem that Tangents from the Same Point Are the Same Length

Question

The tangent OA is 10 cm in length. What is the length of the tangent OB?

Step-by-Step:

1

Tangents drawn from the same point outside of the circle have the same length.

OB = OA = 10 cm

Answer:

The tangent OB has length 10 cm.

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See Also

What is a right triangle? What is a radius? What is a circle? What are the circle theorems?