Aim: How do we graph dilation's?

Answer:

Dilation's:
         -A dilation is a type of transformation that causes an image to stretch(get bigger) or shrink(get smaller) in proportion to its original size.

Examples:







           
                                                                                                                                                                        






Scale Factor:

-The ratio by which the image gets bigger or smaller is known as the scale factor.
-If the scale factor is >1(greater than 1) then the image is enlarged.
-If the scale factor is >0(greater than 0) and <1(less than 1), then the image will shrink.
-Multiply the dimensions of the original image by the scale factor to get the dimensions of the dilated image.

Example:
  (2,1) * D(3)= (6,3)(Dimensions of the dilated image)

Try this yourself:


Under a dilation, triangle A(0,0), B(0,4), C(6,0) becomes triangle A'(0,0), B'(0,10), C'(15,0).  What is the scale factor for this dilation?   Choose one:
2
2.5
4
                                                                                                    Answer: 2.5



Find the image of (6,-4) under the dilation D(3).
 A) (7,4)
 B) (18,-12)
C)  (3, -2)
 D) (9,-6)

To practice more on dilations visit: http://regentsprep.org/Regents/math/geometry/GT3/PracCoD.htm