4/26 Dilation Practice

A dilation is which of the following: 

• only an enlargement

• only a reduction

• Either an enlargement or a reduction

• Neither an enlargement or a reduction

When a dilation has a scale factor greater than one, the dilation is an enlargement.

• True

• False

When the scale factor of a dilation is less than one, the dilation is a reduction.

• True

• False

State the coordinate of the image of the given point B (4,9) under a dilation with center at the origin with the given scale factor of 2.

• B' (2 , 4.5)

• B' (-8 ,-18)

• B' (8 ,18)

• B' (9 ,4)

What is the algebraic representation for this dilation?

• ( x , y ) --> ( 3/2 x , 3/2 y )

• ( x , y ) --> ( 1.5 x , 1.5 y )

• ( x , y ) --> ( 2/3 x , 2/3 y )

• ( x , y ) --> ( 0.33 x , 0.33 y )

What is the algebraic representation for this dilation?

• ( x , y ) --> ( 2 x , 2 y )

• ( x , y ) --> ( x -2 , y -2 )

• ( x , y ) --> ( x +2 , y + 2 )

• ( x , y ) --> ( 1/2 x , 1/2 y )

What is the algebraic representation for this dilation?

• ( x , y ) --> ( 1/2 x , 1/2 y )

• ( x , y ) --> ( 2 x , 2 y )

• ( x , y ) --> ( 1/2 x , 2 y )

• ( x , y ) --> ( 2 x , 1/2 y )

What is the algebraic representation for this dilation?

• ( x , y ) --> ( 25 x , 25 y )

• ( x , y ) --> ( 0.25 x , 0.25 y )

• ( x , y ) --> ( 2.5 x , 2.5 y )

• ( x , y ) --> ( x , y )

What variable represents scale factor in the algebraic representation (x,y) to (kx,ky)?

• x

• y

• z

• k

What is the scale factor in the algebraic representation
(x,y) to (2x,2y)

• k=2

• k=1/2

• k=2.2

• k=0.5