Lesson Topic The Area of Parallelograms Through Rectangle

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Lesson Topic: The Area of Parallelograms Through Rectangle Facts Lesson Objective: I can… Show

Lesson Topic: The Area of Parallelograms Through Rectangle Facts Lesson Objective: I can… Show the area formula for the region bounded by a parallelogram by composing it into rectangles. Understand that the area of a parallelogram is the area of the region bounded by the parallelogram.

Review What are some examples of quadrilaterals? Rectangles, squares, trapezoids, parallelograms How do we

Review What are some examples of quadrilaterals? Rectangles, squares, trapezoids, parallelograms How do we find the area of a rectangle? Base times height What must be true about the relationship between the base and the height? They must be perpendicular (form a right angle), and the height must come from a vertex opposite the base. The height may be the side of a shape, or it may lie inside or outside the shape.

Review What makes a quadrilateral a parallelogram? It has 2 sets of parallel lines

Review What makes a quadrilateral a parallelogram? It has 2 sets of parallel lines True or false: A rectangle is a parallelogram. True, but calling it a rectangle is more specific How to the shape. Predict: can we find the are of a parallelogram?

Let’s discover and prove the area formula for parallelograms…

Let’s discover and prove the area formula for parallelograms…

Discussion We know the formula for the area of a rectangle is Area =

Discussion We know the formula for the area of a rectangle is Area = base x height. What is the formula to calculate the area of a parallelogram? The same as a rectangle, A = bh Why is the height the vertical line and not the slanted edge? If we look back to the rectangle we created, the base and height of both the rectangle and the parallelogram are perpendicular to each other. So, the height of a parallelogram is the perpendicular line drawn from the top base to the bottom base.

A Different Example… How could we construct a rectangle from this parallelogram? Why can’t

A Different Example… How could we construct a rectangle from this parallelogram? Why can’t we use the same method we previously used? Where is the base and where is the height?

Options: 1. 2. Practice – Pull up exercises on today’s Power. Point on your

Options: 1. 2. Practice – Pull up exercises on today’s Power. Point on your i. Pad and record in your notebook or on a separate sheet of paper Compose parallelograms into rectangles by cutting and re-arrange their parts like shown in today’s lesson.

Exercises

Exercises

Exercises, cont.

Exercises, cont.

Exercises, cont.

Exercises, cont.

- Why are the area formulas for rectangles and parallelograms the same? - It

- Why are the area formulas for rectangles and parallelograms the same? - It does not matter how tilted a parallelogram is, the formula to calculate the are will always be the same as the area formula of a rectangle.

Evaluate Your Learning 4 3 2 1 How will you “Sharpen Your Saw”?

Evaluate Your Learning 4 3 2 1 How will you “Sharpen Your Saw”?