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<title>Explanation of Two Circles Touching Externally</title>
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<h1>Explanation of the Relationship Between TQ and TR</h1>
Let's analyze the given problem step-by-step to understand why TQ = TR is the correct answer.
<h2>Problem Summary</h2>
We have two circles of equal radii that touch externally at a point P. From a point T on the common tangent at P, tangent segments TQ and TR are drawn to the circles with points of contact Q and R respectively.
<h2>Diagram and Geometry</h2>
To correctly visualize the problem, consider the following setup:
- Two circles with centers O<sub>1</sub> and O<sub>2</sub> and radius r.
- The circles touch externally at point P.
- A common external tangent at P intersects a point T.
- Tangent segments TQ and TR are drawn from point T touching the circles at points Q and R respectively.
<h2>Geometric Properties of Tangents</h2>
We use the following key properties of tangents to circles:
- Tangent segments drawn from an external point to a circle are equal in length.
- Tangent segments from a common external point to two touching circles are equal, due to the congruence of the tangents.
<h2>Mathematical Reasoning</h2>
Let's denote the lengths of TQ and TR as follows:
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TQ = TR
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This is due to the fact that both TQ and TR are tangent segments drawn from the same external point T to the points of contact Q and R on respective circles. Because tangents from an external point to a circle are equal, and the circles touch externally, segments TQ and TR must be equal.
<h2>Conclusion</h2>
Thus, we conclude that the correct relationship between TQ and TR is:
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TQ = TR
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Therefore, the correct answer to the multiple-choice question is:
<h2>References and Further Reading</h2>
For more in-depth understanding of circle tangents and properties, you can refer to renowned geometry textbooks such as:
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