Happy Monday 1.Pick up notes from the front table. 2.Take out your HW #1 and 7.1 notes. Tonight’s...

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Transcript of Happy Monday 1.Pick up notes from the front table. 2.Take out your HW #1 and 7.1 notes. Tonight’s...

Happy Monday

1. Pick up notes from the front table. 2. Take out your HW #1 and 7.1 notes. Tonight’s Homework• P 465 # 1-6, 11, 13-18

- Start your Project (due next Monday)Update: Quiz #1 ( 7.1-7.3) • Thursday/Friday

Agenda

Go over Homework and 7.1 word problems7.2: Ratios in Similar PolygonsGo over Project

HW #1 ( p 457)Spend four minutes discussing the homework with your table-mates. ( 7.1 word problems and book work)

Write the homework down under HW #1 on your assignment sheet.

Remember: If you forgot/left it at home/dog ate it, this is the time to write 2-3 sentences on why you chose not to do the homework.

HW #1 ( p 457)I am going to use my equity sticks to call on students to state the answer that they got on their homework. It is okay if you got it incorrect!

Make sure you are listening! Listening is a great skill to master!

Whiteboard: Warm-Up!

1. If ∆QRS ∆ZYX, identify the pairs of congruent angles and the pairs of congruent sides.

2. Solve the proportion

7.2: Ratios in Similar Polygons

Learning Objective(1 ) SWBAT identify similar polygons(2) SWBAT apply properties of similar polygons to solve problems

Table-Share

Table-Share:What does it mean if two figures are congruent?

Congruent Figures • Corresponding Angles are….

• Corresponding Sides are…

Figures that are similar (~) have the same shape but not necessarily the same size.

Similar Polygons

Table-Share:What does it mean if two figures are similar

given the definition?

Think: What is the relationship between the angles?What about the sides?

Similar Polygons

• Corresponding Angles are….

• Corresponding Sides are…

What transformation is this?Answer: Similar figures are known as dilations!

7.2: Ratios in Similar Polygons

Similarity ratio ( or scale factor)• ratio of the lengths of the corresponding sides

of two similar polygons• how much the figure is enlarged or reduced – Dilation

7.2: Ratios in Similar Polygons

Similarity statement ( or scale factor)• Order matters just like congruent statements • ( ~ ) is the similarity symbol

Example 1

Example 2 (a): Identifying Similar Polygons

Determine whether the polygons are similar. If so, write the similarity ratio and a similarity statement.

Example 2(b)

Determine whether the polygons are similar. If so, write the similarity ratio and a similarity statement.

Whiteboard

Determine whether the polygons are similar. If so, write the similarity ratio and a similarity statement.

Car Models

Find the length of the model to the nearest tenth of a centimeter.

Whiteboards

A boxcar has the dimensions shown. A model of the boxcar is 1.25 in. wide. Find the length of the model to the nearest inch.

Closure:Whiteboards

Determine whether the polygons are similar. If so, write the similarity ratio and a similarity statement. If not, state why.

Closure

2. The ratio of a model sailboat’s dimensions to the actual boat’s

dimensions is . If the length of the model is 10 inches, what is the length of the actual sailboat in feet?

Closure

Tell whether the following statement is

sometimes, always, or never true and

state why.

Two equilateral triangles are similar.

Project

• Print this project rubric off my website • I only printed one per table so you can read it

With your tables work on the Extra Practice!

What you don’t finish is also homework!

Work With Your Tablemates…

Ms. Huls wants to build a new math room at Leland, but first she wants to see a scale model of the room. • The scale model is 1/3 the size of the real room.• The actual classroom door is 6 ft. tall.• The model’s door is 1 ft. wide.

1. Set up a proportion involving the dimensions of the door.2. How tall is the door in the model?3. How wide is the actual door?4. What is the ratio of the area of the model’s door to the area

of the real door?