Geometry

Question Analysis:
Focus on proof strategy for parallelograms.

Key Concept Explanation:
Parallel opposite sides is the key defining property.

Step-by-Step Solution:
Use slope formula to check if opposite sides have equal slopes.
If both pairs match → it's a parallelogram.

Option Analysis:
A) Parallel sides = direct method → ✅
B) Equal sides could mean rhombus → ❌
C) Right angles = rec...