Geometry

Question Analysis:
This question centers on the property of an equilateral triangle where all sides are of equal length.
The key task is to leverage this property to establish an equation using the given algebraic expressions for the side lengths and subsequently solve for to determine the length of the side.

Key Concept Explanation:
An equilateral triangle is defined by having all three sides congruent.
This characteristic enables us to equate any two of the expressions that denote the side lengths of the equilateral triangle.

Step - by - Step Solution:
1. Because all sides of an equilateral triangle are equal, we set up the equation:
  - .
2. First, we want to get all the terms on one side. Subtract from both sides:
  - .
  - This simplifies to , further reducing to .
3. Next, add 5 to both sides of the equation:
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