Dilations Given a Center and Scale Factor

A triangle has vertices with coordinates (2,0), (3, -1) and (-2,-5). If the triangle is dilated by a scale factor of 3 with the origin as the center of dilation, what are the coordinates of the vertices of the image?

• (5,3), (6,2), (1,-2)

• (6,0), (9,-3), (-6,-15)

• (2/3,0), (1,-1/3), (-2/3,-5/3)

• (-1,-3), (0,-4), (-5,-8)

Tags

CCSS.8.G.A.3

A dilation can produce a smaller figure or a(n)______

• reduction

• enlargement

• scale factor

• center of dilation

Tags

CCSS.8.G.A.3

Which of the following are Dilations?

• (x, y) → (x, 3y)

• (x, y) → (3x, 3y)

• (x, y) → (x, y - 3)

• (x, y) → (.5x, .4y)

Tags

CCSS.8.G.A.3

Does the image show a dilation?

• Yes

• No

Tags

CCSS.HSG.CO.A.2

In the diagram below, CD is the image of AB after a dilation of scale factor k with center E. Which ratio is equal to the scale factor k of the dilation?

• EC : EA

• BA : EA

• EA : BA

• EA : EC

Tags

CCSS.8.G.A.3

Match the following dilations by a scale factor of 1/2.

• (-3, -4)

• (-6,-8)

• (3,4)

• (10,2)

• (0, -5)

• (0, -10)

• (0,0)

• (6,8)

• (5,1)

• (0,0)

Answer explanation

Note that 0/2 is still 0

so (0,0) dilated by 1/2 is still at (0,0)

(0,-10) dilated by a 1/2 is at

(0, -5)

Tags

CCSS.8.G.A.3

What is the scale factor if the triangle on the left is the original?

• 2

• 3/2

• 2/3

• 1/2

Tags

CCSS.7.G.A.1

What is the scale factor if the smaller rectangle is the original rectangle?

• 4

• 25

• 5

• 6

Tags

CCSS.7.G.A.1

What is the scale factor used to dilate the small square to the larger square given there areas?

• 4

• 16

• 3

• 12

Tags

CCSS.7.G.A.1

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

• ½

• ¼

• 4

• 2

Tags

CCSS.8.G.A.3