Unit 3 Creation

Unit 3 Creation: Area of Parallelograms and Triangles

Nicholas Banko

start

Lesson Objectives

I can use a coordinate plane to:Find the area of a parallelogram Find the area of a triangle

I can use a formula to:Find the area of a prallelogramFind the area of a triangle

CONTINUE

Vocab & Discovery

CONTINUE

Vocabulary we will use

Parallelogram - a quadrilateral with two pairs of parallel sides Quadrilateral - A polygon or shape with 4 sides Parallel - A set of lines that will never meet or intersect Base - The bottom of a shape, its horizontal distance Height - How tall the shape is, its vertical distance.

Continue

Thinking of Parallelograms as altered rectangles

• Give students their grid paper and rectangle cutouts
• Have students trace their rectangles on the grid paper and find the area using their own methods
• Prompt students to make a Triangle in their rectangle that goes from a top corner to the bottom base of the shape
• Have students cut their new triangle off of the original rectangle, then place their two new pieces of paper in any configuration they can:
• Did the area of this shape change from the original rectangle?
• Can you arrange these pieces to make a parallelogram
• Model the solution
• Have students trace their new parallelograms on the grid paper and find the area using their own methods.
• Compare qualities of the rectangle and parallelogram using the grid

CONTINUE

Parallelograms

CONTINUE

The Area Formula

• Review findings from the day before:
• What is special about paralellograms?
• How are they related to rectangles?
• Go over how where to find the base of a parallelogram:
• If this were a building, which side would be the floor?
• How long is it?
• Go over how to find the height of a parallelogram:
• Where would the ceiling be with the base we chose?
• How far away is it from our base?
• If I were to drop a rope from the corner of the building, how long would it need to be to reach the ground?
• If this were a rectangle with these dimensions, how would I find the area?
• If I turn this parallelogram back into a rectangle, do my dimensions change?
• Suggest that since a parallelogram is a modified rectangle, the area should be the same:

Area=Base x Height

• Have students practice finding the area of various parallelograms

CONTINUE

Connecting with triangles

CONTINUE

Area of a Triangle

• Have students begin by going to the Shape Geoboard on Toy Theater
• Have students make different triangles and try to find the area of the triangles.
• Discuss strategies
• Model how to create a parallelogram by combining two congruent triangles
• What if I did this?
• Can we find the area of this?
• How can I use the area of this to find the area of my original triangle?
• Review the formula to find the area of a parallelogram:
• Is there a way I can modify my formula to work for triangles?
• Why does that work?
• Area= (Base x Height)/2
• Have students practice finding the area of various triangles

CONTINUE

Assessment

CONTINUE

What Do You Know?

• Have students begin class with Sankaku puzzles with a partner
• Encourage students to use whatever method they want to find the solutions
• After, do a quick review of parallelograms and triangles
• Have students complete lessons on IXL for finding an area of parallelograms (IXL Lesson Y8K) and finding the area of triangles (IXL Lesson C8S)
• Students should work to reach a smart score of 80 or higher on both assignments to demonstrate proficiency in that skill.
• IXL data will provide room to learn from mistakes, practice meaningful examples, and provide data that can be used for differentiated small groups and remediation.

FINISH