The dashed triangle is the image of the solid triangle. The center of dilation is (−4,−4). What is the scale factor used to create the dilation?

enter image source here

1 Answer
Sep 23, 2016

#SF = -3#


Looking at the figure and its image, three things are immediately obvious.....
The image is bigger
The image is inverted.
The figure and the image have a common point.

The common point is the centre of dilation.# (-4,-4)#
The fact that it lies BETWEEN the image and the figure means that the SF is a negative number.
This accounts for the fact that the image is inverted.

To find the Scale Factor divide #("a side in the image")/("the same side in the figure"}#

Looking at the horizontal lines we see..

#("a side in the image")/("the same side in the figure"} = -6/2 = -3#