Parallel sides are two sides of a shape that are always the same distance apart and never meet, no matter how far they are extended.
You can think of parallel sides like railroad tracks—no matter how far they go, they never cross each other.
To identify parallel sides, look for pairs of sides that run in the same direction and will never touch, even if extended with lines.
Parallel sides usually “face” each other. Check both pairs of opposite sides in four-sided shapes.
Different quadrilaterals have different numbers of parallel sides. Knowing this helps you name and classify them.
Quadrilaterals can be grouped by how many pairs of parallel sides they have. This is an important clue to identifying them correctly.
When describing quadrilaterals, use the number of parallel side pairs as part of their definition and classification.
Describing quadrilaterals by their sides makes it easier to see the differences and similarities between shapes.