Circle Transformations

What is the dilation scale factor to transform circle B onto A?

• 9/16

• 4/3

• 3/4

• 1

What is the dilation scale factor to transform circle B onto circle A?

• 3/7

• 7/3

• 5/7

• 5/3

Which graph corresponds to 
(x-8)²+ (y+2)²=

• A

• B

• C

• D

If circle S shown below is translated 3 units to the left and 4 units up, in which quadrant will the center of the circle, point S, lie?

• I

• III

• II

• IV

Circle A has center (2, 7) and radius 2. Circle B has center (9, 1) and radius 5. Which transformations can be used to show that the two circles are similar?

• Translate circle A right 7 and down 6 and then dilate with scale factor 5/2 and center (9, 1)

• Translate circle A left 7, up 6 and then dilate with scale factor 2/5 and center (9, 1).

• Dilate circle A using center (2, 7) and scale factor 2/5 then translate right 7 and down 6

• Reflect circle A over x = 5.5 and translate up 6 units.

Circle B is the pre-image and Circle A is the image. Which transformations map Circle B onto Circle A?

• (x, y)→(x − 4, y + 8); dilation by scale factor of 3/4 at center of circle

• (x, y)→(x + 4, y − 8); dilation by scale factor of 4/3 at center of circle

• (x, y)→(x − 4, y + 8); dilation by scale factor of 4/3 at center of circle

• (x, y)→(x − 4, y + 8); dilation by scale factor of 1/2 at center of circle

Which translation, when applied to the center of the circle x²+y²=4, creates the congruent circle x²+y²+8x-10y+37=0?

• T_4,5

• T_4,-5

• T_-4,-5

• T_-4,5

Two circles A and B have different radii.  A student dilates circle A at its center by a scale factor of 9/4 to make it the same size as circle B.  What scale factor could have been used to make circle B the same size as circle A?

• 3/2

• 2/3

• 4/9

• 9/4

Let there be two circles, circle A and circle B. There exists a translation that can be performed on circle A such that it will have the same center as circle B. There exists a dilation that can be performed on circle B such that it will have the same center as circle A. Thus, there exists a sequence of transformations that can be performed on circle A in order to obtain circle B. ??? Since circle A and circle B can be any circles, all circles are similar. Which statement is best for statement 5?

• Therefore, circle A is similar to circle B.

• Therefore, circle A is congruent to circle B.

• Therefore, circle A is not similar to circle B.

• Therefore, circle B is congruent to circle A.