Answer:
-1/3
Step-by-step explanation:
The scale factor relating similar triangles can be found as the ratio of the lengths of corresponding sides.
A'B'/AB = 2/6 = 1/3
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At the same time it was dilated, the triangle was reflected across the origin. That is, each coordinate of the original triangle was multiplied by -1/3.
The dilation factor was -1/3.
