After completing the Check-your-understanding Questions, which were important for everyone to do?

Start by working in your notebook to figure out the length of the missing sides. After one minute, discuss your work with your seat partner. Take turns. If needed, modify or make changes to your original thinking.

1. Identify missing dimensions

1A

2. Identify missing dimension

2A

To find a missing dimension after breaking up a composite figure:

First, break it into simpler shapes and include the numbers that make sense.

Second, use addition or subtraction to determine the missing sides

Example A: To find the height of the triangle:

Example B: To find the base of the triangle:

Third, verify that you have all the dimensions

What is the area of the composite figure?

1

1A

2

2A

3

3A

4

4A

To calculate the area of a composite figure:

1. Decompose the figure (i.e. break it into simple shapes)

2. Write the dimensions

3. Calculate the areas of each simple shape, and add or subtract them.

1. In your notebook, make meaningful notes for your forgetful selves

2. CYUqs → p721: 1, 2; p723: 11 (Volume 2 Ch9-6)

Do your work in your notebook. Draw the composite figure. Draw the smaller, simple shapes. Include dimensions. Write the formulas and find their areas.

Check answers as you’re working. If you make a mistake, fix it. If you need help, get help. If someone else needs help, give help.

3. Stuck? Choose to persevere: review your thinking, try different approaches, ask for help, search