3.2 How Can I Find the Height? Pg. 6 Heights and Areas of Triangles.

Slides:

Advertisements

Similar presentations

Triangles, Trapezoids & Kites

Advertisements

35° 55° Yes, slope is more than 1 Isaiah, 19° has slope less than 1 Less than 9.

Architects create scaled plans for building houses. Artists use sketches to plan murals for the sides of buildings. Companies create smaller sizes of their.

Volume and Surface Area Make sure you have your mini-lesson paper in front of you. You will know you need to write something on the notes because it will.

An Interactive Book About Math Vocabulary By Mrs. Emmer-Miller.

Graphic artists often need to make a shape larger to use for a sign

Triangles Shape and Space. Area of a right-angled triangle What proportion of this rectangle has been shaded? 8 cm 4 cm What is the shape of the shaded.

Surface Area Return to table of contents.

3.3 How Can I Find the Height? Pg. 9 Heights and Areas of Triangles.

7.2 What’s The Area? Pg. 8 Areas of Circles and Sectors.

4.4 How Can I Use Equivalent Ratios? Pg. 13 Applications and Notation.

4.2 How Can I Use Equivalent Ratios? Pg. 7 Applications and Notation.

3.3 How Can I Find the Height? Pg. 9 Heights and Areas of Triangles.

This chapter opens with a set of explorations designed to introduce you to new geometric topics that you will explore further. You will learn about the.

Resource Managers Did you remember to get the folders? Put the teams homework in the folder on the right side.

4. 4 A B 7 C How Much Does It Hold? Pg. 12 Volume of Prisms and Cylinders 8.4 How Much Does It Hold? Pg. 12 Volume of Prisms and Cylinders.

10.4 Area of Triangles and Trapezoids. You will learn to find the areas of triangles and trapezoids. Nothing new!

10-1: Area of Parallelograms and Triangles Objectives: To find the area of parallelograms and triangles To find the area of parallelograms and triangles.

At the right is a polygon known as a trapezoid. The two parallel sides (horizontal in this case) of the trapezoid are called bases. b1b1 b2b2 b2b2 b1b1.

KNOW WHICH LINE MATTERS WHEN FINDING AREA & VOLUME! IDENTIFYING HEIGHT & BASE.

1.2 How Can We Work Together? Pg. 7 Creating a Quilt Using Symmetry and Investigations.

1.2 What Can We Work Together? Pg. 6 Creating a Quilt Using Symmetry and Investigations.

4.2 What Do These Shapes Have In Common? Pg. 7 Similarity.

A right triangle is a triangle with a right angle

Shape and Space Triangles The aim of this unit is to teach pupils to:

Evaluating Conditions for Congruency

Lesson Concept: Square Units and Area of Rectangles

Section 1.1 – Nets and Drawings for Visualizing Geometry

Multi-View Sketching Multi-View Sketching

Area of a Rectangle = base x height

Lesson – Teacher Notes Standard:

Geometry-Part 5.

Lesson Concept: Relationship of Area and Perimeter

Lesson Concept: Using Rectangles to Multiply

In your work with two‑dimensional (flat) shapes, you have described their dimensions, their perimeters, and their areas. For three‑dimensional shapes.

Geometry 15 Jan 2013 Warm up: Check your homework. For EACH PROBLEM: √ if correct. X if incorrect. Work with your group mates to find and correct any.

Multiview Sketching Multiview Sketching

Area – Learning Outcomes

Multiview Sketching Multiview Sketching

Forging new generations of engineers

Multi-View Sketching Multi-View Sketching

Multi-View Sketching STEM Foundations Multi-View Sketching

Principles of Art Notes Page.

Multi-View Drawings.

Multi-View Sketching Multi-View Sketching

How can a Topographic Profile be Constructed?

Perspective Sketching

Turn to Page S.76 Describe what you know about the triangle listed to the left. What type of triangle is it? What are the labels A , B , and C ? What are.

Triangles and Parallelograms Lesson 11.2

The Week is Almost Half Way Over! Do Now:

Proportions and Similar Figures

DNA 3D Paper Model Directions.

Similar Figures.

Multi-View Sketching Multi-View Sketching

Sketching Multiview Drawings

Area of Triangles.

Multi-View Sketching Multi-View Sketching

Multi-View Sketching Multi-View Sketching

Multiview Sketching Multiview Sketching

Forging new generations of engineers

Sketching Multiview Drawings

2-D Representations of Solids

Sketching Multiview Drawings

Multi-View Sketching Multi-View Sketching

Forging new generations of engineers

Presentation transcript:

3.2 How Can I Find the Height? Pg. 6 Heights and Areas of Triangles

3.2 – How Can I Find the Height?__________ Heights and Area of Triangles Sometimes the height of a shape isn't shown in the picture. Today we are going to examine how to find the height of a shape when it isn't shown.

3.8 –HEIGHT LAB What is the height of a triangle? Is it like walking up any side of the triangle? Or is it like standing at the highest point and looking straight down? Today your team will build triangles with string and consider different ways heights can be seen for triangles of various shapes.

a. Use the materials given to you by your teacher to make a triangle like the one in the diagram below. Be sure to use the team roles listed below.

Resource Manager: Holds the two bottom corners, forming the base of the triangle Facilitator: Makes sure the red string dangles down freely, not touching anything Recorder/Reporter: Sketches the triangles that are created, shares them with the team when group is finished Team Captain: Makes the third point (top point) of the triangle and the height string with pencil or pen

b. Now, with your team, build and sketch triangles that meet the three conditions below.

3.9 –HEIGHT HUNT How can I find the height of a triangle if it is not a right triangle? a. Assume you know the length of the side labeled "base." For each triangle, draw in the height that would enable you to find the area of the triangle. A notecard can be used to translate along the base until you reach the height. Note: You do not need to find the area.

b. For the triangle below, draw all three possible heights. First choose one side to be the base and draw in the corresponding height. Then repeat the process of drawing in the height for the other two sides, one at a time.

base

3.10 –AREA OF SHADED PART Find the area of the shaded figure. Be ready to share any observations.

3.11 –AREA OF A TRIANGLE Isaiah claimed that he didn't need to calculate the area for (b) and (c) because it must be the same as the area for the triangle in part (a). a. Is Isaiah's claim correct? How do you know? Yes, they are all half of the same rectangle

b. Explain why the area of any triangle is half the area of a rectangle that has the same base and height. That is, show that the area of a triangle must be html?movie=/hotmath_help/gizmos/triangleA rea.swf Area of Triangle

They all have the same area

3.12 –AREA OF A TRIANGLE, CONT How do you know which dimensions to use when finding the area of a triangle? a. Find the area of each shaded figure. Draw any lines on the paper that will help. Turning the triangles may help you discover a way to find their areas.

A = ½bh A = ½(21)(12) A = ½(252) A = 126un 2

A = ½bh A = ½(6)(5) A = (3)(5) A = 15un 2

A = ½bh A = ½(7)(8) A = ½(56) A = 28un 2 7 8

b. Look back at your work from part (a). Which numbers from each triangle did you use to find the area? Write an explanation and/or draw a diagram that would help another student understand how to choose which lengths to use when calculating the area. b h

c. Mario, Raquel, and Jocelyn are arguing about where the height is for the triangle below. The three have written their names along the part they think should be the height. Determine which person is correct. Explain why the one you chose is correct and why the other two are incorrect.