To answer this question, let's analyze the conditional and converse forms of each statement and determine which one is true in both forms.

1. Statement A: "If $B$ is the midpoint of $\overline{AC}$, then $AB = BC$."

• Conditional: If $B$ is the midpoint of $\overline{AC}$, then $AB = BC$.
  • This is true because by definition, the midpoint of a segment divides it into two equal parts.
• Converse: If $AB = BC$, then $B$ is the midpoint of $\overline{AC}$.
  • This is also true, because if $AB = BC$, then $B$ divides the segment $\overline{AC}$ into two equal parts, making it the midpoint.

Thus, Statement A is true in both its conditional and converse forms.

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2. Statement B: "If $K$ is between points $J$ and $L$, then $K$ is a midpoint."

• Conditional: If $K$ is between points $J$ and $L$, then $K$ is a midpoint.
  • This is false because just because $K$ is between $J$ and $L$, it does not necessarily mean $K$ divides the segment into two equal parts. $K$ could be anywhere along the line between $J$ and $L$, not necessarily at the midpoint.
• Converse: If $K$ is the midpoint of $\overline{JL}$, then $K$ is between $J$ and $L$.
  • This is true because the midpoint of a segment is always between the two endpoints.

Thus, Statement B is false in its conditional form, so it cannot be the correct answer.

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3. Statement C: "If two angles are right angles, then they are congruent."

• Conditional: If two angles are right angles, then they are congruent.
  • This is true because all right angles are congruent by definition. Each right angle measures 90°.
• Converse: If two angles are congruent, then they are right angles.
  • This is false because two angles can be congruent without being right angles. For example, two angles of 45° are congruent but not right angles.

Thus, Statement C is false in its converse form.

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4. Statement D: "If a polygon has 3 sides, then the sum of its interior angles is 180°."

• Conditional: If a polygon has 3 sides, then the sum of its interior angles is 180°.
  • This is true because the sum of the interior angles of a triangle (3-sided polygon) is always 180°.
• Converse: If the sum of the interior angles of a polygon is 180°, then the polygon has 3 sides.
  • This is true because only a triangle has an interior angle sum of 180°.

Thus, Statement D is true in both its conditional and converse forms.

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Conclusion:

The statement that is true in both its conditional and converse forms is Statement A: "If $B$ is the midpoint of $\overline{AC}$, then $AB = BC$".

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Would you like further explanations on any of the steps? Here are some related questions for you to consider:

1. How do we determine the midpoint of a line segment mathematically?
2. What is the definition of congruent angles, and how can they be proved in geometry?
3. How does the formula for the sum of the interior angles of a polygon work for polygons with more than three sides?
4. What are some examples of polygons where the interior angle sum is different from 180°?
5. How can we use the converse of a statement in geometric proofs?

Tip: When analyzing conditional statements and their converses, always check whether the converse is logically valid by considering counterexamples.