CIRCUMFERENCE ~D AREA OF A CIRCLE. remember that the diameter = 2 x radius. , Circumference of a :circle = 11 x diameter DATE: PERIOD: N~ :

Transcription

1 CIRCUMFERENCE ~D I AREA OF A CIRCLE, Circumference of a :circle = 11 x diameter remember that the diameter = 2 x radius N~ : DATE: PERIOD:

2 A circle is all points in the same plane that lie at an equal distance from a center point. The circle is only composed of the points on the border. You could think of a circle as a hula hoop. It's only the points on the border that are the circle. The points within the hula hoop are not part of the circle and are called interior points. The distance between the midpoint and the circle border is called the radius. A line segment that has the endpoints on the circle and passes through the midpoint is called the diameter. The diameter is twice the size of the radius. A line segment that has its endpoints on the circular border but does not pass through the midpoint is called a chord.

3 e circumference of a circle following circles: C =nd =3.14x4 - C = 2nr =2x3.14x9 c =nd :3.14 X 23 C = 21tr, :2 X 3.14 X 58 em

4 Course 2: 7th Grade Circles Name ID: ~---- Lesson I Notes Show ALL Your Work Date Period Find the circumference of each circle. Round your answer to the n~arest tenth. 1) 2) 6 yd 3) 4) Find the circumference of each circle. Round your answer to the nearest whole. 5) 8) Find the area of each. Round your answer to the nearest tenth. 9) 10) 3

5 11) 12) 8 in Find the area of each. Round your answer to the nearest whole. 13) 14) 10m 6km 15) 16) 7 yd Find the diameter of each circle. Round your answer to the nearest tenth. 17) 18) 5m

6 5 19) 20) 7.3mi 6.5mi Find the diameter of each circle. Round your answer to the nearest whole. 21) 22) 23) 24) 6mi Find the circumference of each circle. Round your answer to the nearest tenth. 25) radius= 8 km 26) radius= 8.6 em 27) radius = 9 em 28) radius = 4 ft Find the area of each. Round your answer to the nearest whole. 29) diameter= 8 mi 30) diameter= 6 yd 31) diameter= 16 km 32) diameter= 12 in

7 Course 2: 7th Grade Circles Name ID: Classwork #1 Show ALL Your Work Date Period --~---- Find the circumference of each circle. Round your answer to the nearest tenth. 1) 2) 9mi 3) 4) 12m Find the circumference of each circle.. Round your answer to the nearest whole. 5) 6)

8 7) 8) 15 em Find the area of each. Round your answer to the nearest tenth. 9) 10) 11) 12) 7 yd 3.7mi

9 Find the area of each. Round your answer to the nearest whole. 13) 14) 15) 16) 12 km 11 yd Find the diameter of each circle. Round your answer to the nearest tenth. 17) 18) 10.3 m 19) 20) 9.9 km

10 Find the diameter of each circle. Round your answer to the nearest whole. 21) 22) 2 in 23) 24) Find the circumference of each circle. Round your answer to the nearest tenth. 25) radius = 6 em 26) radius = 8 mi 27) radius= 7.4 yd 28) radius= 3.5 in Find the area of each. Round your answer to the nearest whole. 29) diameter= 17 km 30) diameter= 15 em 31) diameter = 22 mi 32) diameter= 18 km

11 Course 2: 7th Grade Circles Name ID: ~ Homework #1 Show ALL Your Work Date Period Find the circumference of each circle. Round your answer to the nearest tenth. 1) 2) 3) 4) 4.5cm Find the circumference of each circle.. Round your answer to the nearest whole. 5) 6) }0

12 7) 8) 10ft _6km Find the area of each. Round your answer to the nearest tenth. 9) 10) 9km 11) 12) 2mi 10 mi '- I J I

13 Find the area of each. Round your answer to the nearest whole. 13) 14) 2mi 15) 16) Find the diameter of each circle. Round your answer to the nearest tenth. 17) 18) 7.6mi 19) 20) 5mi 3 ini

14 Find the diameter of each circle. Round your answer to the nearest whole. 21) 22) 12in 23) 24) 5km Find the circumference of each circle.. Round your answer to the nearest tenth. 25) radius = 12m 26) radius= 11.4 in 27) radius = 4.4 km 28) radius = 4 m Find the area of each. Round your answer to the nearest whole. 29) diameter= 16 in 30) diameter= 10m 31) diameter = 8 ft 32) diameter= 22 km /3

15 A.rea & Circumference Find. the exact area and circumference of each circle. 2) 3) Radius= Diameter= Area; Circumference = Radius= Diameter"" Area"" Circumference = Radius= 0Jameter 1 = Areai= Circumference!=. 4) 5) 6).. v ti-~1'~ ~. '. /... ~.// ->,"ii:l, /.... ~ ' './ ' ' ED Radius= Diameter= Area= Circumference = Radius"" Diameter= Area= Circumference = Radius= Diameter- Area== Circumference= 7) 8) 9) Radius=--- Diameter=----- Area=---- Circumference= Radius=--- Diameter=---- Are.a =---- Circumference = Radius=--- Diameter=----- Area= Circumference =.

16 Findin the Circumference of a Circle Find the circumference of each circle. Circles are not to scale. 1) 2) Name: Answers I ) 4) ) 6) ) 8) 9) 10) t: Math :l: 15

17 Fin din the Area. of a Circle Find the area of each circle. Circles are not to scale. 1) 2) Name: Answers ) 4) ) 6) ) 8) 9) 10) --~M-a-th--~ ~ ~--~~~~

18 Findin the Area and Circumference of a Circle Find the area and circumference of each circle. Circles are not to scale. 1) 2) Name: Answers la. lc. 2a. 3) 4) 2c. 3a. 3c. 4a. 5) 6) 4c. Sa. Sc. 6a. 7) 8) 6c. 7a. 7c. 8a. 9) 10) 8c. 9a. 9c. loa. t: Math :l.. I loc. '. 17: ~' '' ~;,