Have you ever noticed how many different kinds of cell phones there are? Sometimes you might have a cell phone that is similar to one of your friends’

Slides:



Advertisements
Similar presentations
Scaling Up Investigation 4.2. Warm Up Solve the following problems. 1. X = There are 450 students and 15 teachers in a school. The school hires.
Advertisements

Architects create scaled plans for building houses. Artists use sketches to plan murals for the sides of buildings. Companies create smaller sizes of their.
Connection to previews lesson… Previously, we studied rigid transformations, in which the image and preimage of a figure are congruent. In this lesson,
Section 8.3 Similar Polygons
Congruence and Similarity
Graphic artists often need to make a shape larger to use for a sign
Transformations Dilations Translations Reflections Rotations.
Similar Triangles and other Polygons
In Lesson 6.1.2, you used words and coordinate points to describe how a triangle moved on a graph.  These expressions described the starting place, the.
Ch 3 Spiral Review.
Dilations Shape and Space. 6.7 cm 5.8 cm ? ? Find the missing lengths The second picture is an enlargement of the first picture. What are the missing.
Scale Factor.
Dilations Section 9.7. Dilation A dilation is a transformation that stretches or shrinks a figure to create a similar figure. A dilation is not an isometry.
Take two minutes to list words that come to mind when you hear the word dilation. Enlarging or reducing a figure is called dilation.
Properties of Dilations, Day 2. How do you describe the properties of dilations? Dilations change the size of figures, but not their orientation or.
Introduction Rigid motions can also be called congruency transformations. A congruency transformation moves a geometric figure but keeps the same size.
Objectives Define and draw lines of symmetry Define and draw dilations.
Remember that when an object is translated, rotated, or reflected, it stays the same size and shape even though it moves.  For this reason, these types.
All scale drawings must have a scale written on them. Scales are usually expressed as ratios. Normally for maps and buildings the ratio: Drawing length:
4.2 How Can I Use Equivalent Ratios? Pg. 7 Applications and Notation.
andand Similarity ShrinkingShrinking StretchingStretching.
2.5 How Can See It? Pg. 17 Kaleidoscopes and Central Angles.
In geometry, two objects are similar when one is a scale model of the other. SIMILAR SHAPES.
Have you ever wondered how different mirrors work? Most mirrors show you a reflection that looks just like you. But other mirrors, like the mirrors commonly.
4.4 What Information Do I need? Pg. 14 Conditions for Triangle Similarity.
Stretching and Shrinking
 Answer the following in complete thought sentences.  You can use your notes from the other day.  What happens to the side lengths, perimeter and area.
Similar Figures and Scale Drawings
How can you see growth in the rule?
Lesson Concept: Relationship of Area and PerimeterArea 1 You now have learned a lot about area (the number of square units that are needed to cover.
Lesson – Teacher Notes Standard: 7.G.A.1 Solve problems involving scale drawings of geometric figures, including computing actual lengths and areas.
Quick Start Expectations 1.Pick up new HWRS and fill in HW: SS p #5-7, # Get a signature on HWRS 3.On desk: journal, HWRS, pencil, pen 4.Warm.
Transparency 5 Click the mouse button or press the Space Bar to display the answers.
 When figures have the same size and shape we say they are congruent.  In this lesson I will focus on congruent triangles.
4.2 What Do These Shapes Have In Common? Pg. 7 Similarity.
1 As you learned from enlarging the CPM Middle School mascot in Lesson 4.2.1, an image is enlarged correctly and keeps its shape when all measurements.
Similarity and Ratios Investigation 4
You have been looking at geometric patterns and ways in which those patterns can be represented with x→y tables, graphs, and equations. In Lesson 4.1.2,
1 What if you wanted to enlarge the dragon mascot from Lesson to make it big enough to fit on the side of a warehouse? What if you wanted to make.
Take out your homework and math journals Check your homework and record effort on your half sheet. Be ready to start class at 11:08 – with your math journals.
In Chapter 4, you worked with writing and simplifying expressions. As you wrote expressions, you learned that it was helpful to simplify them by combining.
1 Variables are useful tools for representing unknown numbers. In some situations, a variable represents a specific number, such as the hop of a frog.
1 In this chapter, you have developed several different strategies for finding the areas of shapes. You have found the sums of the areas of multiple smaller.
Holt Geometry Warm Up Find the area of each figure. Give exact answers, using  if necessary. 1. a square in which s = 4 m 2. a circle in which r = 2 ft.
2-46. WARM-UP STRETCH Today you will investigate a transformation called a dilation that enlarges or reduces a figure while maintaining its shape. After.
Looking Ahead p. 3. Looking Ahead p. 4 SS Inv. 1.1 SS Inv. 1.2 Vocabulary: SimilarScale drawingImage Corresponding sidesCorresponding Angles.
Similar Figures Investigation 2 YMLA Pre AP Math
TRANSFORMATIONS. DEFINITION  A TRANSFORMATION is a change in a figure’s position or size.  An Image is the resulting figure of a translation, rotation,
A right triangle is a triangle with a right angle
8.2.7 Dilations.
Math CC7/8 – Be Prepared On Desk: Pencil Learning Log: Math Journal
Do Now: ≅
Chapter 4 – Scale Factors and Similarity Key Terms
MATH 8 – UNIT 1 REVIEW.
Ratios, Rates and Percents
SIMILAR POLYGONS Two figures are similar if
Warm Up.
Students will be able to dilate shapes
Make your new weekly Warm up Page
Slope and Similar Triangles
Chapter 10 Similarity.
Warm Up I will give 20 minutes to finish homework and ask questions
Warm-up.
Lesson – Teacher Notes Standard: 7.G.A.1
Day 84 – Enlargement.
Parts of Similar Triangles
Make your new weekly Warm up Page
Transformations Dilations Translations Reflections Rotations.
Year 11 Maths 12th and 13th June 2019.
Splash Screen.
Presentation transcript:

Have you ever noticed how many different kinds of cell phones there are? Sometimes you might have a cell phone that is similar to one of your friends’ cell phones because it is the same brand, but it might be a different model or color. Occasionally, two people will have the exact same cell phone, including brand, model, and color. Sorting objects into groups based on what is the same about them is also done in math. As you work with your team to sort shapes, ask the following questions: How do the shapes grow or shrink? What parts can we compare? How can we write the comparison?

6-64. WHICH SHAPES ARE SIMILAR? If two shapes appear to have the same general relationship between sides, how can you decide for sure if the shapes are similar? Work with your team to: Carefully cut out the original shape and shapes A through G from one copy of the Lesson Resource Page. Lesson Resource Page Decide how each shape is related to the original shape. (Each person should use an uncut copy of the resource page and the team’s cut out shapes to help decide.) Compare the angles and the sides of shapes A through G to the original shape.

6-64. WHICH SHAPES ARE SIMILAR? a)Which shapes are similar to the original shape? Give specific reasons to justify your conclusions. b)Now look only at the shapes that are similar to the original shape. What do these shapes have in common? What is different about them? Be specific. c)When two shapes are similar, the scale factor is the number you multiply the length of the side of one shape by to get the length of the corresponding side of the new shape. What is the scale factor between the original shape and shape E? Is each side of the shape enlarged the same number of times? Use a ruler to help you decide, if needed. d)What is the scale factor between the original shape and shape C? Why is it less than 1?

6-65. Shapes that are similar but do not grow or shrink are called congruent shapes. a)Which shape from problem 6-64 is exactly equal to the original shape in every way? b)Record the pairs of shapes below that appear to be congruent to each other.

6-66. Quan enlarged shape Q to make shape P, below. Are his shapes similar? If they are similar, identify the scale factor (multiplier). If they are not, demonstrate that at least one pair of sides does not share the scale factor.

6-67. Draw each of the shapes in problem 6-66 on graph paper. Color-code the corresponding sides on each shape using the colors suggested by your teacher. a)Compare the green sides of each shape. What do you notice about those sides? b)Compare each of the other five sides of shape P with their corresponding sides on shape Q. What do you notice about those pairs of sides? c)Imagine enlarging shape P to make a new shape R that has a base 25 units long. If shape R is similar to shape P, predict the length of the shorter vertical side of shape R without drawing the shape. What is the scale factor in this situation?

6-68. Using the triangle shown at right as the original figure, predict which of the scale factors below would enlarge (make bigger) or reduce (make smaller) the shape. (Do not actually make a new shape.)

6-68 Divide up the scale factors from the previous problem among your teammates. Copy the original triangle and then create your new triangle with your assigned scale factor. a)Show your new triangle to your teammates and check your predictions. Which scale factors made the triangle larger? Which made the triangle smaller? Is there a pattern? b)Which parts of the new triangles remained the same as the original triangle? Which parts changed? How do you know? c)Each of the new triangles is similar to the original triangle used to create it. Compare the corresponding (matching) sides and angles to each other. Describe the relationship or explain why you think there is no relationship. d)What scale factor could you use to create a triangle that is congruent to the original? Explain. e)Additional Challenge: Find a scale factor that will make a similar shape that is larger than the original but has a scale factorless than 2.

6-69. LEARNING LOG In your Learning Log, explain how to determine when shapes are similar. To decide if two shapes are similar, what do you need to know about the side lengths? The angles? Title your entry “Finding Similar Shapes” and include today’s date.