new image scale factor = original 1.determine whether the...

Geometry Honors: Unit 7 Day 4 Similarity Transformations

!!!!!!!!!!!!!!!!! Scale Factor =

1. Determine whether the dilation from Figure A to Figure B is an enlargement or a reduction.

Then find the scale factor of the dilation.

Learning Target - In geometry, transformation refers to the movement of objects in the coordinate plane.Transformations can be used to verify similarity in polygons.

Success Criteria: 1. I can identify a series of transformations to prove or disprove that two given figures are similar. I can use

the triangle bisector theorem. 2. I can explain using similarity transformations the meaning of similarity for triangles as the equality of all

corresponding pairs of angles and the proportionality of all corresponding pairs of sides.

New ImageOriginal

a. !

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b.!

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2. A photocopy of a receipt is 1.5 inches wide and 4 inches long. By what percent should the receipt be enlarged so that its image is 2 times the original? What will be the dimensions of the enlarged image? !!!!

3. a. Graph the original figure and its dilated image. Then verify that the dilation is a similarity transformation. Original: M(–6, –3), N(6, –3), O(–6, 6) New image: D(–2, –1), F(2, –1), G(–2, 2) !!!!!!!

b. Graph the original figure and its dilated image. Then verify that the dilation is a similarity transformation.

Original: V(1, 5), W(0, 2), X(4, 3) New image: Y(-2, -4), Z(10, -1)

!

!!!!!!4. Mariano wants to enlarge a picture he took that is 4 inches by 7.5 inches. He wants it to fit perfectly into a frame that is 400% of the original size. What will be the dimensions of the enlarged photo? !!!5. Sam is painting a sign with dimensions of 4 inches by 10 inches and used ! bottle of paint. Sam

needs to also paint a sign with dimensions of 1 foot by 2 ft 6 inches. The signs are similar. !a. Explain how the second sign is a dilation of the first sign. !!b. How many bottles of paint will Sam need to complete the second sign?

d = x2 − x1( )2 + y2 − y1( )2

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