Thursday, February 23 rd

1. Thursday, February 23rd Warm Up The length of a rectangle is 14 in, the width 6 in, and the height 3 in. Find the Volume Find the surface Area Please complete warm up and write down the Homework  Take out homework (Prism worksheet)

2. Joke of the Day What bird is good at making bread? A “dough dough”

3. Homework Answers Think, Pair, Share

4. Goal for today Volume and Surface Area CYLINDERS

5. How would you describe: Net Of a Cylinder?

6. Circle Review

7. Radius Center A line segment with one endpoint at the center of the circle and the other endpoint on the circle is a radius (plural: radii). It is half the diameter

8. Radius Center Diameter A diameteris a line segment that passes through the center of the circle and has both endpoints on the circle. The length of the diameter is twice the length of the radius.

9. Circumference Radius Center Diameter The distance around a circle is called the circumference.

10. Circumference The formula for the circumference of a circle is C = d, or C = 2r.

11. tttttttttttt Area

12. Part 1: Surface Area Using a Net Using a Formula

13. Nets for Cylinder Cylinders- the net for a cylinder is made of two congruent circles, and one rectangle. • The circumference of the circle is the length of the rectangle

14. Just Watch Area of Circle: πr² 3 x 5² 3 x 25 75 2 circles: 75 x 2 = 150 Area of Rectangle: L x W Length= circumference Length= 2πr Length= 2 x 3 x 5 Length = 6 x 5 Length = 30 Area =30 x 10 Area = 300 2 Areas=600 600 + 150=750

15. #1 Try Together Area of 2 Circles: Area of Rectangle:

16. #2 You Try Area of 2 Circles: Area of Rectangle:

17. #3 You Try Area of 2 Circles: Area of Rectangle:

18. Surface Area with Formulas

20. #1 Try Together SA= 2 πr² + 2πrh SA=__________+__________+__________ SA=__________+__________+__________ • SA=__________+__________+__________ SA=_________

21. #2 Try Together SA= 2 πr² + 2πrh SA=__________+__________+__________ SA=__________+__________+__________ • SA=__________+__________+__________ SA=_________

22. #3 You Try SA= 2 πr² + 2πrh SA=__________+__________+__________ SA=__________+__________+__________ • SA=__________+__________+__________ SA=_________

23. #4 You Try SA= 2 πr² + 2πrh SA=__________+__________+__________ SA=__________+__________+__________ • SA=__________+__________+__________ SA=_________

24. Part 2: Volume

25. To find the volume of a cylinder, you can use the same method as you did for prisms: Multiply the area of the base by the height. volume of a cylinder = area of base  height The area of the circular base is r2, so the formula is V = Bh = r2h.

26. Write the formula. Replace with 3, r with 4, and h with 7. Multiply. V336 V3427 The volume is about 336 ft3. Just Watch V = r2h

27. 10 cm ÷ 2 = 5 cm Find the radius. Write the formula. Replace with 3, r with 5, and h with 11. Multiply. V825 V35211 The volume is about 825 cm3. #1 Try Together V = r2h

28. Multiply. V540 The volume is about 540 ft3. Write the formula. Replace with 3, r with 6, and h with 5. V3625 #2 You Try 6 ft 5 ft V = r2h

29. Multiply. V288 8 cm ÷ 2 = 4 cm The volume is about 288 cm3. Find the radius. Write the formula. Replace with 3, r with 4, and h with 16. V3426 #3 You Try 8 cm 6 cm V = r2h

30. 3-2-1 Summary 3 things you learned 2 things you still need practice on 1 Which way do you like finding surface area: net or formula