1.4 Dilations

1.4 Dilations

Dilations will enlarge or reduce your image on the coordinate plane. 

Remember!

Poll

Which transformations do you like the most so far?

• Translations (Slides)

• Reflections (Flips)

• Dilations (Stretch or shrinks)

• Rotations (Turns)

Multiple Choice

A scale factor of 1/2 reduces a figure.

• True

• False

Multiple Choice

The "image" is the shape before the dilation.

• True

• False

Multiple Choice

The _________ is the ratio of a length of the new figure to the corresponding length on the original figure.

• reduction

• enlargement

• scale factor

• center of dilation

Multiple Choice

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

• True

• False

Multiple Choice

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

• True

• False

Multiple Choice

When the scale factor is negative, what happens to the figure?

• Enlarges

• Reduces

• Reflects

• Rotates 180 degrees

Fill in the Blanks

Multiple Choice

If the triangle ABC is dilated using a scale factor of k=2, what will be the coordinates of A' after the transformation?

(Click the picture to enlarge it)

• A'(1.5, -1.5)

• A' (-6, 6)

Multiple Choice

A(1,2) is a point on a triangle. If the triangle is dilated by a scale factor of k =4, what is the coordinate of A'?

• A' (0.25, 0.5)

• A' (-4, -8)

• A' (4, 8)

Multiple Choice

What is the image of K(6, 8) after a dilation of k = 1/2 ?

• K' (4, 3)

• K' (12, 16)

• K' (3, 4)

Multiple Choice

What is the image of D (-6, 4) after a dilation of k = 3 ?

• D' (18, 12)

• D' (-18, 12)

• D' (-18, -12)

Poll

How do you feel about dilations?