Triangle ABCTriangle ABC is transformed with the center of dilation at the origin. Pre-image: △ABC with vertices A(−5, −4), B(−
7, 3), C(3, −2) Image: △A′B′C′ with vertices A′(−3.75, −3), B′(−5.25, 2.25), C′(2.25, −1.5) What is the scale factor of the dilation that maps the pre-image to the image?
2 answers:
Pre Image having vertices : △ABC with vertices A(−5, −4), B(−7, 3), C(3, −2)
Image having vertices : △A′B′C′ with vertices A′(−3.75, −3), B′(−5.25, 2.25), C′(2.25, −1.5).
As, Size of Preimage > Size of image
So, 0<Dilation Factor <1
When a triangle is dilated , the preimage and image are similar to each other .
Scale factor can be get through by finding the ratio of any of corresponding sides of triangle.
So, Scale Factor of Dilation =
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