Dilations
Find the Side
Similarity
Which Triangle?
DOUBLE POINTSπ°
100

Enlarging or reducing a figure.

What is dilation?

100

What is the formula we use to find the missing side for similar triangles?

BIG/SMALL = BIG/SMALL

OR

SMALL/BIG=SMALL/BIG

100

True or false: Similar figures have the same SHAPE, but could have different sizes.

True

100
How many degrees do the 3 angles of a triangle add up to equal?

180

100

NAME AND DESCRIBE 1 of the 3 triangle similarity theorems we've learned about in Unit 2C.

AA, SSS, SAS

200

When k>1, what happens?

Enlargment

200

DOUBLE JEOPARDY!!!!!!!!!

PLACE YOUR BID! I WILL REVEAL THE QUESTION! π

50 FEET

200

LOOK AT #8!!!!!!!!!!!! πππ

Triangle KLM is the pre-image of ΞKβLβMβ before a transformation.

Are the two triangles similar?

YES

200

In triangle ABC, angle A is 45β° and angle B is 50β°.

TRUE OR FALSE: Triangle DEG where angle D is 45β° and angle E is 85β°.

TRUE

200

The two triangles below are similar. Find the measure of y.

80 DEGREES

300

Triangle GHJ with vertices G(-2, 4), H(3, 6), and J(3, -2) is dilated by a factor

of π

π

centered at the origin. What are the coordinates of G' after the dilation?

(-1/2, 1)

300

LOOK AT #3!!!!!!!!!!!!! πππ

Lloyd is standing near a power line pole as shown in the figure. When his head touches the support wire, he is 2 1/2 feet from where the wire meets the ground.

If the power line pole is 17 feet tall, how tall is Lloyd?

5 FEET

300

CHALLENGE!!!

For an extra 300 points, select a problem from the review and work it on the board with your team. Teach it to the class in less than 2 minutes.

Challenge Accepted! 300 POINTS!!!!!!!!!!!

300

In triangle ABC, angle A is 45β° and angle B is 50β°.

TRUE OR FALSE: Triangle MNO where angle N is 45β° and angle O is 60β°.

FALSE

300

LOOK AT #10!!!!!!!!!!!!!! ππ

The two triangles below are similar. Find the measure of x.

53 DEGREES

400

LOOK AT # 2!!!!! πππ

Polygon MNPQ is shown on the coordinate plane. A dilation centered about the origin will be performed on the polygon.

The location of the vertex M after the dilation is (-8,6). What is the location of vertex Q after the dilation?

(-4,-4)

400

LOOK AT #5!!!!!!!!!!!! ππ

Triangle PQR is similar to triangle EDC.

What is the length of segment CD?

78 inches

400

LOOK AT #8!!!!!!!!!!!! πππ

Triangle KLM is the pre-image of ΞKβLβMβ before a transformation.

Paul said that ΞABC was dilated by a scale factor of 1.5 centered at the origin. Is Paul CORRECT?

π¨π¨π¨(If no, what is the scale factor).π¨π¨π¨

No, the scale factor is about 1.6

400

In triangle ABC, angle A is 45β° and angle B is 50β°.

TRUE OR FALSE: Triangle GHI where angle G is 50β° and angle I is 85β°.

TRUE

400

LOOK AT #11!!!!!!!!!!!!!!!! ππ

Which of the following reasons justifies Step 3?

1. Angle-Angle (AA) Similarity

2. Reflexive Property of Congruence

3. Vertical angles are congruent.

4. Corresponding angles are congruent.

Corresponding angles are congruent.

500

LOOK AT #7!!!!!!!!!!! ππ

In the xy-coordinate plane, ΞABC has vertices A(7,3), B(5, -1), and C(4, 5) and ΞDEF has vertices Aβ(3, 3), Bβ(2, 1), and Cβ(1.5, 4). The triangles are similar because ΞDEF is the image of ΞABC under a dilation.

Which two statements are TRUE About the transformation of ΞABC?

C. The center of dilation is at (-1, 3).

E. The scale factor is 2.

500

Joey built a model sailboat that is similar to his real sailboat. The triangular sail on his real boat has a base of 25 feet. If the height of the sail on his model boat is 12 inches and the base is 24 inches, what is the height of the sail on his real boat?

12 1/2 FEET

500

In the coordinate plane, line p has slope 8 and y-intercept (0, 5). Line r is the result of dilating line p by a factor of 4 with center (0, 3).

What are the slope and y-intercept of line r?

C. Line r has slope 8 and y-intercept (0, 11)

500

In triangle ABC, angle A is 45β° and angle B is 50β°.

TRUE OR FALSE: Triangle PQR where angle Q is 45β° and angle R is 50β°.

TRUE

500

LOOK AT #11!!!!!!!!!!!!!!!! ππ

What should be the STATEMENT FOR Step 5?