Grade 4 - Progress in Mathematics

Parallel and Perpendicular Lines

10-3

A E D

C B

F

H J I

G

K

M

L

N

Write intersectingor parallelto describe each pair of lines.

Intersecting lines are lines that meet

or cross at a common point.

AB



and CD



intersect

at point E.

Perpendicular lines are intersecting lines

that form four right angles.

Read: line FGis perpendicular toline HI

Write: FG



HI



Parallel lines are lines in the same plane

that never intersect.

Read: line KLis parallel toline MN

Write: KL



MN



Line segments can also be intersecting,

perpendicular, or parallel.

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