Dilations Review

• If a is greater than 1, the image of the polygon is congruent to the polygon.

• If a is between 0 and 1, the image of the polygon is congruent to the polygon.

• If a is greater than 1, the image of the polygon is smaller than the polygon.

• If a is less than 1, the image of the polygon is smaller than the polygon.

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)

Dilations have which operation?

• Addition

• Subtraction

• Multiplication

• Division

Which of the following algebraic rules represents an enlargement?

• (x, y) --> (3x, 3y)

• (x, y) --> (0.5x, 0.5y)

• (x, y) --> (0.75x, 0.75y)

• (x, y) --> (0.999x, 0.999y)

• (x, y) --> (5x, 5y)

A transformation is applied to create a new figure. Which transformation does NOT preserve congruence?

• A reflection across the x-axis

• A translation 7 units down

• A dilation by a scale factor of 5

What type of dilation is shown?

• enlargement

• reduction

What is the scale factor for the given dilation?

• 2

• 5

• 1

What is the algebraic representation/rule for the dilation shown?

What type of dilation is shown?

• enlargement

• reduction

What is the algebraic representation/rule for the dilation shown?