Geometry

Question Analysis:
This question involves determining when a parallelogram becomes a square.
The main focus is on having both equal sides and right angles.

Key Concept Explanation:
A square is both a rhombus (equal sides) and a rectangle (right angles).
If one angle is 90°, and all sides are congruent, the parallelogram is a square.

Step-by-Step Solution:
We are told all sides are congruent, so the figure is already a rhombus.
To become a square, the angle must be 90°.
Set the equation:
2x + 10 ...