Dilations STAAR Review

A figure with the coordinates A(3,3) B(6,6) C(9,3) is dilated by a scale factor of 3 with the origin as the center of dilation. What are the coordinates of the image?

• A'(9,9) B'(18,18) C'(27,9)

• A'(6,6) B'(9,9) C'(12,6)

• A'(0,0) B'(3,3) C'(6,0)

• A'(1,1) B'(2,2) C'(3,1)

Polygon ABCDE will be dilated by a scale factor of 2.  Which statement is NOT true of the dilation?

• The corresponding angles of the two polygons will be equal.

• The dilation will be an enlargement.

• The original and the image will be congruent.

• Polygon A'B'C'D'E' will be proportional to polygon ABCDE. 

The pre-image, MNOP, has vertices M(2,1.5),N(2, 4),O(5, 4), P(5,1.5). A transformation is applied

to create the image, M’N’O’P’, which has vertices M'(8,6), N'(8,16), O'(20,16), P'(20,6). Which

rule represents this transformation?

• 
• 
• 
• 

When you dilate, you ______ x and y by a number.

• Multiply

• Add

• Subtract

• Divide

Dilations are ________ but not congruent.

• Similar

• Flipped

• Rotated

• Congruent

The point A (8, 12) was dilated to become point A' (2, 3). What was the scale factor?

• ½

• ¼

• 4

• 2

How do you write the algebraic notation when the scale factor is 3?

• (x, y) --> (1/3x, 1/3y)

• (x, y) --> (-3x, -3y)

• (x, y) --> (x + 3, y + 3)

• (x, y) --> (3x, 3y)

A dilation is which of the following: 

• An enlargement

• A reduction

• Either an enlargement or a reduction

• Neither an enlargement or a reduction

State the coordinate of the image of the given point B (-10,-6) under a dilation with center at the origin with the given scale factor k = 1/2.

• (5,3)

• (20,12)

• (-20,-12)

• (-5,-3)

A scale factor of less than one means

• that the new image will be larger than the old image.

• That the new image will be the same as the old image.

• That you need to subtract that amount off of each side.

• That the new image will be a reduction of the new image.