1.7 Constructions 2010
October 18, 2010
1 ­ 7
Constructions
Objectives:
• Use a protractor to measure angles.
• Use a straightedge and compass to construct congruent segments and angles.
• Use a straightedge and compass to construct a perpendicular bisector and an angle bisector.
Aug 31­9:37 PM
1
1.7 Constructions 2010
October 18, 2010
Constructions
Today we will be working on constructions. In a construction you use a straightedge and a compass to draw a geometric figure.
Materials Needed Today:
• straightedge (ruler with no markings on it)
• compass
• protractor
Aug 31­9:37 PM
2
1.7 Constructions 2010
October 18, 2010
Using your straightedge, draw two different angles. One that is acute and the other obtuse. Label each angle as acute or obtuse.
Using your protractor, measure each angle.
Aug 31­9:40 PM
3
1.7 Constructions 2010
October 18, 2010
Using your straightedge and protractor, draw three angles measuring 60o, 90o, and 130o.
Aug 31­9:42 PM
4
1.7 Constructions 2010
October 18, 2010
Constructing Congruent Segments
B
A
Aug 31­9:43 PM
5
1.7 Constructions 2010
October 18, 2010
Constructing Congruent Angles
A
B
C
Aug 31­9:43 PM
6
1.7 Constructions 2010
October 18, 2010
Constructing a Perpendicular Bisector
B
A
Aug 31­9:43 PM
7
1.7 Constructions 2010
October 18, 2010
Constructing an Angle Bisector
A
Aug 31­9:44 PM
8
1.7 Constructions 2010
October 18, 2010
Homework
page: 47
#'s: 1­8, 41­50
Aug 31­9:44 PM
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