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Thursday, February 23 rd. 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). Joke of the Day.
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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)
Joke of the Day What bird is good at making bread? A “dough dough”
Homework Answers Think, Pair, Share
Goal for today Volume and Surface Area CYLINDERS
How would you describe: Net Of a Cylinder?
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
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.
Circumference Radius Center Diameter The distance around a circle is called the circumference.
Circumference The formula for the circumference of a circle is C = d, or C = 2r.
tttttttttttt Area
Part 1: Surface Area Using a Net Using a Formula
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
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
#1 Try Together Area of 2 Circles: Area of Rectangle:
#2 You Try Area of 2 Circles: Area of Rectangle:
#3 You Try Area of 2 Circles: Area of Rectangle:
#1 Try Together SA= 2 πr² + 2πrh SA=__________+__________+__________ SA=__________+__________+__________ • SA=__________+__________+__________ SA=_________
#2 Try Together SA= 2 πr² + 2πrh SA=__________+__________+__________ SA=__________+__________+__________ • SA=__________+__________+__________ SA=_________
#3 You Try SA= 2 πr² + 2πrh SA=__________+__________+__________ SA=__________+__________+__________ • SA=__________+__________+__________ SA=_________
#4 You Try SA= 2 πr² + 2πrh SA=__________+__________+__________ SA=__________+__________+__________ • SA=__________+__________+__________ SA=_________
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.
Write the formula. Replace with 3, r with 4, and h with 7. Multiply. V336 V3427 The volume is about 336 ft3. Just Watch V = r2h
10 cm ÷ 2 = 5 cm Find the radius. Write the formula. Replace with 3, r with 5, and h with 11. Multiply. V825 V35211 The volume is about 825 cm3. #1 Try Together V = r2h
Multiply. V540 The volume is about 540 ft3. Write the formula. Replace with 3, r with 6, and h with 5. V3625 #2 You Try 6 ft 5 ft V = r2h
Multiply. V288 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. V3426 #3 You Try 8 cm 6 cm V = r2h
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