Question

Given that the area of a circle varies as the square of its radius and that the area of the circle is 616sq. cm when the radius is 14 cm find the area of circle whose radius is 5.25 cm​

Answer 1

Answer:

If area of a circle varies with square of radius.

It means it is direct variation.

As we know in direct variation:

$\frac{x}{y} = k$

So,

$\frac{616}{14²} = \frac{x}{5.25²}$

$\frac{22}{7} = \frac{10000x}{275625}$

$\frac{22 \times 275625}{7 \times 10000} = x$

x = 86.625cm²

Area of circle is 86.625cm².

Mark me brainliest.

Answer 2

Given that the area of a circle varies as the square of its radius and that the area of the circle is 616sq. cm when the radius is 14 cm find the area of circle whose radius is 5.25 cm

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Area of the circle is = 616sq

The radius is = 14 cm

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Radius = 5.25 cm

Area of the circle is = ?

__________________________

Area of circle of radius = 5.25 cm = π r²

= 22/7 × 5.25 × 5.25

= 86 . 625 cm ²

___________________________

Some formula of Circle :

1. Area of circle = π r ²
2. Radius = C / 2π