Dilations

What is the formula for scale factor?

Dilate the figure by a scale factor of 3. What are the coordinates of the image?

A(3,3) B(6,6) C(9,3)

• 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)

Dilate Point B by a scale factor of 3:

• (12,0)
• (12,12)
• (4,3)
• (0,12)

Triangle ABC will be dilated by a scale factor of 1/2.  What will be the coordinates of C'?

• (-1, -2.5)
• (12, 6)
• (3, -1.5)
• (0, 1.5)

Enlargement or reduction?  Find the scale factor!

• It's a reduction; the scale factor is 2.
• It's an enlargement; the scale factor is 2.
• It's an enlargement; the scale factor is 1/2.
• It's a reduction; the scale factor is 1/2.

Enlargement or reduction?  Find the scale factor!

• It's an enlargement; the scale factor is 1/2.
• It's an enlargement; the scale factor is 2.
• It's a reduction; the scale factor is 1/2.
• It's a reduction; the scale factor is 2.

Trapezoid A’B’C’D’ is the dilation of trapezoid ABCD.

Which algebraic representation shows this dilation?

• (x, y) --> (2x, 2y)

• (x, y) --> (0.5x, 0.5y)

• (2x, 2y) --> (x, y)

• (x, y) --> (3x, 2y)

A ~ B. What is the scale factor of the dilation of A to B?

• 3

• 4

Does the image show a Dilation and what is the scale factor?

• Yes; k = 2

• Yes; k = 1/2

• No, it's a translation.

• No, it's a reflection.

ABC ~ XYZ. What is the scale factor of the dilation of ABC to XYZ?

• 2

• 3