Parallel and Perpendicular Lines

Front

What are parallel lines?

Back

Lines that never meet and are always the same distance apart.

Front

What are perpendicular lines?

Back

Lines that intersect at a right angle (90 degrees).

Front

What is a horizontal line?

Back

A line that goes from left to right and is flat.

Front

What is a vertical line?

Back

A line that goes up and down.

Front

Identify the lines that are horizontal: SP and RQ, SR and PQ, SR and MK, RQ and MN.

Back

SR and PQ.

Front

Identify the lines that are vertical: SP and RQ, SR and PQ, SR and MK, RQ and MN.

Back

SP and RQ.

Front

What is the symbol for parallel lines?

Back

The symbol || is used to denote parallel lines.

Front

What is the symbol for perpendicular lines?

Back

The symbol ⊥ is used to denote perpendicular lines.

Front

If two lines are parallel, what can be said about their slopes?

Back

Their slopes are equal.

Front

If two lines are perpendicular, what can be said about their slopes?

Back

The product of their slopes is -1.