Dilations

Dilations are a change in....

• size

• orientation

• rotation

• shape

If a dilation has a scale factor bigger than one, the shape

• stretches

• shrinks

• stays the same

• gets smaller

If the shape has a k factor less than one, the shape

• stretches

• shrinks

• doesn't changeg

• gets bigger

If the shape has a k factor of 3, you ...

• Divide by 3

• Add 3

• Subtract 3

• Multiply by 3

A shape with the k factor of 0....

• makes the shape disappear

• makes the shape get larger

• makes the shape infinite

• makes you divide by 0

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.

Tags

CCSS.7.G.A.1

Triangle ABC has vertices A (-2, 2), B (2, 4) and C (3, -1).  What are the coordinates of A' after a dilation by a scale factor of 2.5?

• (-5, 5)

• (5, -5)

• (5, 10)

• (7.5, -2.5)

Tags

CCSS.8.G.A.3

Rectangle ABCD is dilated so that A' is located at (3, 6).  What could be the dilation rule?

• (2x, 3y)

• (2/3 x, 2/3 y)

• (3/2 x, 3/2 y)

• (x + 2, y + 3)

Tags

CCSS.HSG.CO.A.2

Rectangle ABCD is dilated so that the coordinates of C' are (2, -1).  What could be the dilation rule?

• (-2x, +1y)

• (1/2 x, 1/2 y)

• (2x, 2y)

• (x - 2, y - 1)

Tags

CCSS.HSG.CO.A.2

The algebraic expression for an enlargement by a scale factor of 3 is...

• (x, y)→(3x, 3y)

• (x, y)→(3, 3)

• (3x, y)→(x, y)

• (x, y)→(3x)

Tags

CCSS.HSG.CO.A.2