Similarity and Dilations

What is the scale factor from triangle ABC to triangle DEF?

• 1/2

• 7/3

• 2/1

• 10/3

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

• 2

• 3

What is the scale factor from ABCD to MNOP?

• 2/3

• 3/2

• 2

• 3

What is Dilation?

• Dilation means to enlarge or reduce a shape

• Dilation means to flip over a line

• Dilation means two figures that look alike

• Dilation means to make a shape smaller

A triangle has vertices with coordinates A(2,0), B(3, -1) and C(-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 C'?

• (1,-2)

• (-6,-15)

• (-2/3,-5/3)

• (-5,-8)

State the coordinate of the image of point B (-10,-6) after a dilation with a scale factor of 1/2.

• (5,3)

• (20,12)

• (-20,-12)

• (-5,-3)

If two figures are similar, the corresponding angles are...

• Congruent

• Supplementary

• Proportional

• Different

Tell whether the two figures are congruent or similar.

• Congruent, because their sides are the same.

• Congruent, because their sides are proportional.

• Similar, because their sides are the same.

• Similar, because their sides are proportional.

• They are not congruent or similar.

Tell whether the two figures are congruent or similar.

• Congruent, because their sides are the same.

• Congruent, because their sides are proportional.

• Similar, because their sides are the same.

• Similar, because their sides are proportional.

• They are neither congruent or similar.

How are the triangles similar?

• AA

• SAS

• SSS

• NEI or Not Similar