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Lesson 3: Parallel and perpendicular

# Parallel and perpendicular lines review

Review the basics of parallel and perpendicular lines.  Identify and draw parallel and perpendicular lines in some practice problems.

## What are $\greenD{\text{perpendicular lines}}$start color #1fab54, start text, p, e, r, p, e, n, d, i, c, u, l, a, r, space, l, i, n, e, s, end text, end color #1fab54 and $\purpleD{\text{parallel lines}}$start color #7854ab, start text, p, a, r, a, l, l, e, l, space, l, i, n, e, s, end text, end color #7854ab?

start color #1fab54, start text, P, e, r, p, e, n, d, i, c, u, l, a, r, space, l, i, n, e, s, end text, end color #1fab54 are lines that meet at right angles.
Two lines that meet at right angles.
start color #7854ab, start text, P, a, r, a, l, l, e, l, space, l, i, n, e, s, end text, end color #7854ab are always the same distance apart from each other — no matter how far they are extended, they will never meet.
Two lines that will never cross.

## Practice set 1: Identify parallel and perpendicular lines

Problem 1A
• Current
Which of the following pairs of sides in triangle, G, A, Z are perpendicular?
A triangle GAZ. The angle at Z has a box at its vertex connecting lines AZ and GZ. The angles at G and A are acute angles.