Download presentation

Presentation is loading. Please wait.

Published byZachary Hart Modified over 2 years ago

1
Dilations: (Stretching/Shrinking) Dilations use a scale factor to reduce or enlarge shapes. Every dilation has a center and a scale factor. Most of the time it is the origin (0, 0) Scale Factor: tells you how many times larger or smaller your image will be. The new shape and the image are similar. Dilations are also called similarity transformations.

2
Finding a Dilation To find a dilation with center C and scale factor n, you can use the following two rules. The image C is itself (meaning C’=C) For any point R, R’ is on CR and CR’ = nCR.

3
How do we locate dilation images? A dilation is a transformation who preimage and image are similar. A dilation is not an isometry. Every dilation has a center and a scale factor n, n >0. The scale factor describes the size change from the original figure to the image.

4
Example 1: Quadrilateral ABCD has vertices A(-2, - 1), B(-2, 1), C(2, 1) and D(1, -1). Find the coordinates of the image for the dilation with a scale factor of 2 and center of dilation at the origin. A B C A’ B’ C’ D D’

5
Example 2: F(-3, -3), O(3, 3), R(0, -3) Scale factor 1/3 F O R F’ O’ R’

6
Example 3: T(-1, 0), H(1, 0), I(2, -2), S(-2, -2) Scale factor 4 TH I T’ H’ I’ S S’

7
The dilation is an enlargement if the scale factor is > 1. The dilation is a reduction if the scale factor is between 0 and 1.

8
Finding a Scale Factor The blue triangle is a dilation image of the red triangle. Describe the dilation. The center is X. The image is larger than the preimage, so the dilation is an enlargement.

9
Finding a Scale Factor The blue quadrilateral is a dilation image of the red quadrilateral. Describe the dilation.

10
Graphing Dilation Images ∆PZG has vertices P(2,0), Z(-1, ½), and G (1, - 2). What are the coordinates of the image of P for a dilation with center (0,0) and scale factor 3? a) (5, 3)b) (6,0) c) (2/3, 0)d) (3, -6)

11
Graphing Dilation Images Solution: The scale factor is 3, so use the rule: (x, y) (3x, 3y). P(2,0) P’(32, 30) or P’(6, 0). The correct answer is B. The correct answer is B. What are the coordinates for G’ and Z’?

Similar presentations

Presentation is loading. Please wait....

OK

Dilations in the Coordinate Plane

Dilations in the Coordinate Plane

© 2018 SlidePlayer.com Inc.

All rights reserved.

Ads by Google

Ppt on online marketing concept Presentations ppt online form Cg ppt online registration 2012 Ppt on indian politics swami Ppt on vitamin d deficiency Ppt on rivers of india in hindi Ppt on forward contract What does appt only means in spanish Ppt on kinetic theory of matter/gas laws Ppt on different occupations in the medical field