$$$A, B, C$$$ and $$$D$$$ are points on the circle, centre $$$O$$$. Angle $$$A B D=21^{\circ}$$$ and $$$C D=12 \mathrm{~cm}$$$. Calculate the area of the circle. ...................................... $$$\mathrm{cm}^{2}$$$

Mathematics

IGCSE&ALevel

CAIE

Exam No：0580_w20_qp_41 Year：2020 Question No：4(c)

Answer:

130 nfww or $129.6$ to $129.8$

Knowledge points:

E4.7.10 angles in the same segment are equal

E4.7.6 angle in a semicircle

E6.2.1 Apply Pythagoras’ theorem and the sine, cosine and tangent ratios for acute angles to the calculation of a side or of an angle of a right- angled triangle. (Angles will be quoted in degrees. Answers should be written in degrees and decimals to one decimal place.)

E6.2.2 Solve trigonometric problems in two dimensions involving angles of elevation and depression.

E6.2.3 Know that the perpendicular distance from a point to a line is the shortest distance to the line.

$$\(A, B, C\)$$ and $$\(D\)$$ are points on the circle, centre $$\(O\)$$. Angle $$\(A B D=21^{\circ}\)$$ and $$\(C D=12 \mathrm{~cm}\)$$. Calculate the area of the circle. ...................................... $$\(\mathrm{cm}^{2}\)$$

Answer:

Knowledge points:

Solution:

$$\(A, B, C\)$$ and $$\(D\)$$ are points on the circle, centre $$\(O\)$$. Angle $$\(A B D=21^{\circ}\)$$ and $$\(C D=12 \mathrm{~cm}\)$$. Calculate the area of the circle. ...................................... $$\(\mathrm{cm}^{2}\)$$

Answer:

Knowledge points:

Solution:

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