6th Grade Math Textbook, Progress

Use the figure at the right.

1. Name a line that is parallel to
   the given line.

a. AC b. EF

c. AD d. AB

2. Name all the lines that form a pair of skew lines withAD.









Update your skills. See pages 17 and 18.

Lines and Angles

10-2

is parallel to

is perpendicular to

This symbol

indicates a

right angle.

Lines that do not intersect may or may not lie in the same plane.

They are either parallel or skew.

ABand EFare in the same plane.

They are parallel lines.

AB

EF

ABand CGare in different planes.

They are skew lines.

Angles can be classified according to their degree measures.

right acute obtuse straight

x°
90° 0°x°90° 90°x°180° x°
180°

Perpendicular lines are two lines in the same

plane that intersect to form right angles.

AB⊥CD













E F

D C

H G

A B

x° x° x°

x°

A D

C B

F

E

C

B

A

D

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