Geometry

What is Geometry? By Alan Kagan Lesson 1: Area of squares and rectangles

Menu Use the menu to the left to navigate around this PowerPoint to the various sections. Key Exploration of Sides S Sources ? What is Geometry? Act. Area Activity Area of a Rectangle AREA Area of a Square AREA

What is Geometry? Geometry is the study of 2-D and 3-D shapes. Traits such as angles and the number of sides (or surfaces) are used to classify shapes. Click on the shapes to hear their names!

How many sides do I have? Click on the image below and count the sides of the square. Let's count them out loud! 1 2 3 4

Count the sides… Can you count the sides of the shapes? 1 2 3 0 2 1 4 3

Count the sides… Can you count the sides of the shapes? 6 7 8 5 18 15 24 21 Challenge!

Area of a Square How do we find area of a square? Length Width To find the area (or the amount of space on the surface of the shape), we use the simple equation: Length x Width = Area (squared in., squared ft. etc.)

Area of a Square Example: 2 in. 2 in. 2 in. 2 in. = 4 sq. in. Square not drawn to scale

Area of a Square Now it’s your turn! Find the area of the square below. 5 in. 5 in. What is the area of this square? 5 sq. in. 15 sq. in. 25 sq. in. 35 sq. in. Square not drawn to scale

Area of a Square Let’s try one more… Find the area of the square below. 1 ft. What is the area of this square? 1 sq. ft. 2 sq. ft. 4 sq. ft. 8 sq. ft. 1 ft. Square not drawn to scale

Area of a Rectangle How do we find area of a rectangle? Length Width To find the area of a rectangle (or the amount of space on the surface of the shape), we use the same simple equation: Length x Width = Area (squared in., squared ft. etc.)

Area of a Rectangle Example: 2 in. 4 in. 2 in. 4 in. = 8 sq. in. Square not drawn to scale

Area of a Rectangle Now it’s your turn! Find the area of the rectangle below. 4 in. 8 in. What is the area of this rectangle? 4 sq. in. 8 sq. in. 16 sq. in. 32 sq. in. Square not drawn to scale

Area of a Rectangle Let’s try one more… Find the area of the rectangle below. 5 ft. 25 ft. What is the area of this rectangle? 25 sq. ft. 75 sq. ft. 125 sq. ft. 175 sq. ft. Rectangle not drawn to scale

How many squares can I fit? Now that you are an expert on area of squares and rectangles, can you use that knowledge to estimate how many small squares you can fit into a larger square? Let's Find Out!

How Many Squares Fit? To start, it helps to look at the length and width of both squares. 1 ft. 1 ft. 5 ft. 5 ft. Rectangle not drawn to scale

How Many Squares Fit? Now, how would you figure out how many red squares would fit into the blue square? 1 ft. 1 ft. 5 ft. 5 ft. How many red squares do you think will fit into the blue square? How do you know this? Let's find out! Rectangle not drawn to scale

How Many Squares Fit? 1 ft. 1 ft. 5 ft. 5 ft. Let’s count the number of red squares that can fit into the blue square. Rectangle not drawn to scale 1 2 3 4 5 6 7 3 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

Why is it important to know area? Gardening Construction Installing carpet, tiles Table Cloths/ Sheets Can you think of any more reasons?

In Class Activity Now, look around the room for square or rectangular objects. Use a ruler to measure the objects and use a calculator for any big numbers. Make a chart and write down the name of the object, shape, length, width, equation and area of the object. ( REMEMBER TO USE LABLES. ) 100 sq in. 10 in. x 10 in. = 100 sq. in. 10 in. 10 in. Square Window 24 in. Width 432 sq. in 18 in x 24 in.= 432 sq. in. 18 in. Rect. Desk Area Equation Length Shape Object

Sources http://en.wikipedia.org/wiki/Geometry http://www.nctm.org/standards/focalpoints.aspx?id=326 “ Mr. Smith’s Tiling Company” accompanying WebQuest made by Alan Kagan http://zunal.com/webquest.php?user=12191

Geometry

More Related Content

What's hot

Viewers also liked

Similar to Geometry

Recently uploaded

Geometry