Bell Ringer: Standard
• Explain in your own words the following. Also give the proper notation of how to use if applicable
 Point
 Line Segment


Ray
Line


Plane
Collinear
 Coplanar
 Parallel Lines
 Perpendicular Lines
 Vertex
 Angle

Bell Ringer
• Finish this statement
– The notation for ______________ is confusing for me because…
• Example: The notation for angles is confusing for me because I forget to put the vertex as the middle point out of the three points
– Do as many statements as you need

Homework Review
• This is also quiz review, ask questions.
– Worksheet and Textbook questions

More Practice
• Work in small groups to complete the worksheet “All Transformations”

Dilations
A dilation is a transformation that changes the size but not the shape of an object or figure.

Scale Factor
• The ratio between two geometric figures
• How much the figure will dilate
• Example:

Are Dilations Similar or
Congruent?
• Similar – they have the same angles, but not the same size
• Similar show with a
“ ∼ ”

Dilations
To dilate an object:
1) Graph object
2) Multiply the coordinates of the object by the scale factor
3) Graph new coordinates

Example 1:
Dilations

Dilations

Dilations
Your turn:
There is a triangle called △ QRS with points at
Q (0,0)
R (1, 2)
S ( 3, 2)
Dilate the figure by a scale factor of 3

Can a dilation shrink?

Classwork/HW
• Pages 498
 1-5
 All Transformations Worksheet
 All

Exit Ticket
• Which transformations are similar and which are congruent? How do you know?
Explain for each?