GEOMETRY AIM #2-7 (Teachers)

Properties

100

All rigid motions map lines to _____, segments to _________, and rays to _____.

All rigid motions map lines to lines, segments to segments, and rays to rays.

200

All rigid motions preserve _________ and ________ measurements.

All rigid motions preserve distance and angle measurements.

300

Rotation of a line _____ about a point not on the line produces a ___________ line.

Rotation of a line 180 about a point not on the line produces a parallel line.

400

Rotation of a line _____ about a point that does lie on the line produces the ________ line.

Rotation of a line 180 about a point that does lie on the line produces the same line.

500

Translation of a line not along the line produces a __________ line.

Translation of a line not along the line produces a parallel line.

Exercise 1&2

100

Measure the angles of <BEC and <AED

138 degrees

200

What rigid motion can you use to map and BEC and angle AED?

Rotation of 180 about point E

300

What do we know about the measures of vertical angles?

They are congruent

400

Exercise 2: In the diagram below find the value of x

x= 18

500

Find the measure of angle <ZST

<=48

Exercise 3

100

Find the measure of <CFE and <BEF

60 degrees

200

What is the relationship between angle CFE and BEF?

Alternate Interior Angles

300

What is the measure of angle FEB and GFD?

60 degrees

400

What is the relationship between angle FEB and GFD?

Corresponding Angles

500

Thus <FEB = <GFD  because

a rigid motion has been found that maps <FEB onto <GFD