A chord of length 24 cm is at a distance of 5 cm from the centre of a circle. What is its area?
Let the radius of the circle = r
Length of the chord = 24 cm
The perpendicular from the centre to the chord bisects the chord
$$=$$>Â BA = AC = 12 cm
From the figure
In $$\triangle\ $$OAB,
$$OA^2+AB^2=OB^2$$
$$=$$> Â $$5^2+12^2=r^2$$
$$=$$> Â $$25+144=r^2$$
$$=$$> Â $$r^2=169$$
$$=$$> Â $$r=13$$ cm
Radius of the circle = 13 cm
$$\therefore\ $$Area of the circle = $$\pi\ r^2=\frac{22}{7}\times\left(13\right)^2=\frac{22}{7}\times169=531.14cm^2$$
Hence, the correct answer is Option C
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