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Area of CirclesArea of Circlesand Elipsesand ElipsesStage 6 - Year 12Stage 6 - Year 12

General Mathematic(HSC)

2

Area of Circle

Radius

Area = r2

5 cm= x 52

= 25 cm2 (Exact)

≈ 78.54 cm2(Approx)2 decimal place

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3

60o 5 cm

Area of Sector

r

Area = x r2

≈ 13.1 cm2(Approx)1 decimal place

360

Area = x x 5260

360

Fraction of the circle.

Area of the circle.

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4

Area of an Annulus

Area = R2

= x 52

= 21 cm2 (Exact)

≈ 65.97 cm2(Approx)2 decimal place

Rr- r2

5cm2cm

- x 22

Annulus Grass Garden

Area of Large circle.

Area of small circle.

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5

3cm

4cm

Area of an Ellipse

Area = ab

= x 3= 12 cm2 (Exact)

≈ 37.7 cm2(Approx)1 decimal place

x 4a

b

Drawing an EllipseEnd ofEnd ofShowShow