Geometry

Question Analysis:
This problem involves algebraic side lengths.
Focus is on using congruent sides to solve for a variable.

Key Concept Explanation:
A rhombus has all sides equal, so AB = AD.

Step-by-Step Solution:
Set:
2x + 3 = x + 6
Solve:
2x – x = 6 – 3 → x = 3

Option Analysis:
Only B satisfies the rhombus condition.
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