Par Avion Air Mail A I R M A I L Module 4 Lesson 13 Find areas by decomposing into rectangles or completing composite figures to form rectangles. YOUR NAME 1c

Skip counting Let’s skip count by 3s to

Skip counting Let’s skip count by 6s to

Skip counting Let’s skip count by 8s to

Skip counting Let’s skip count by 9s to

FIND THE COMMON PRODUCTS 1. FOLD YOUR PAPER IN HALF. 2. ON THE LEFT HALF, List the multiples of 4 t ON THE RIGHT HALF, list the multiples of 8 to DRAW LINES TO MATCH MULTIPLES THAT APPEAR IN BOTH COLUMNS. `

LEFT SIDE RIGHT SIDE __ X 4 = = ___ X THUMBS UP IF YOUR PAPER LOOKS LIKE THIS. WRITE THE COMPLETE EQUATIONS NEXT TO THEIR PRODUCTS THUMBS UP WHEN YOU’RE DONE

2 X 4 = 1 X 8 4 X 4 = 2 X 8 6 X 4 = ____ X 8 WRITE THE REMAINING EQUALS FACTS AS FULL EQUATIONS WRITE THE REMAINING EQUALS FACTS AS FULL EQUATIONS 8 X 4 = ____ X 8 10 X 4 = ___ X 8 DO FIVE JUMPING JACKS WHEN YOU’RE FINISHED DO FIVE JUMPING JACKS WHEN YOU’RE FINISHED WHAT PATTERN DO YOU NOTICE IN YOUR EQUATIONS? WHAT PATTERN DO YOU NOTICE IN YOUR EQUATIONS?

Problem of the Day Andrew finds the area of a 5-inch by 17-inch rectangle by breaking it into two smaller rectangles. Show one way that he could have solved the problem. What is the area of the rectangle?

Concept Development Part 1: Add using the break apart strategy to find the area of a composite shape.  Give 1 large grid to each student. How do you find the area of a rectangle? Can we find the area of this figure by multiplying the side lengths?

In the problem of the day, we used the break apart strategy to find the area of the larger rectangle. Turn and talk to your neighbor, How many we use a strategy like that to find the area of the shaded figure? We could break it into a square and a rectangle Or we can break it into 3 squares. What are the side lengths of the top square? What are the side lengths of the bottom rectangle? What can we do with the areas of the two shapes to find the total area of the composite figure? What is the total area?

We can also find the area of the shaded figure by thinking of it as a 4 x 4 square with missing units. How can we find the area of the shaded area using the un-shaded square? (4 x 4) – (2 x 2) = 16 – 4 = 12 square units!

Part 2: Subtract to find the area of a composite shape. The figure shows a small rectangle cut out of a larger, shaded rectangle. How can we find the area of the shaded figure? WE can break apart the shaded part. Or we can subtract the un-shaded area from the shaded square.

Pretend we shade in the white rectangle. We now have a large, shaded square. Write a number sentence to find the area of the large square. 6 x 6 = 36 Beneath the number sentence you just wrote, write a number sentence for the shape (white rectangle) we cut out. 2 x 4= 8 The area of the square is 36 square centimeters. We cut out, or took away, 8 square centimeters of shading. How can we find the area of the shaded region? The area of the square is 36 square centimeters. We cut out, or took away, 8 square centimeters of shading. How can we find the area of the shaded region? Write a number sentence to find the area of the shaded region.

Problem 3: Subtract to find the area of a composite shape with unknown side lengths. This figure also shows a small rectangle cut out of a larger, shaded rectangle, but what is unknown? This figure also shows a small rectangle cut out of a larger, shaded rectangle, but what is unknown? The side lengths of the smaller rectangle. The side lengths of the smaller rectangle. Do we have enough information to find the side lengths of the smaller rectangle? Do we have enough information to find the side lengths of the smaller rectangle? Opposite sides of a rectangle are equal. Since we know the length of the rectangle is 9 feet, what is the opposite side length? Opposite sides of a rectangle are equal. Since we know the length of the rectangle is 9 feet, what is the opposite side length? 9 ft

You can find the unknown lengths, by subtracting the known four feet from the total 9 feet. 9 – 4 = 5 feet is the unknown side length! Use the same strategy to find the unknown width. 11 – 5 = 6 feet! Can we now find the area of the shaded figure? Talk with your table how we can now find the area for the shaded figure. What is the area?

Problem Set