Question

2. Find the radius of a circle whose area is twice the area of a circle of radius
14 cm

Answer 1

Step-by-step explanation:

Area of circle whose radius = 14 (πr^2)

$\frac{22}{7} \times 14 \times 14 = 616 {cm}^{2}$

According to Area of first circle is twice of second area of circle = 616x2= 1232cm^2

Redius of cicle when area is given =

$\frac{area}{\pi} = {r}^{2} \\ {r}^{2} = \frac{ \frac{1232}{22} }{7} \\ {r}^{2} = \frac{1232}{1} \times \frac{7}{22} = 392 \\ r = \sqrt{392 = } 19.79approx$

Answer 2

Gɪᴠᴇɴ:

• Area of a circle of a radius ⇒ 14 cm

Fɪɴᴅ:

• Radius of Circle which area is twice

Sᴏʟᴜᴛɪᴏɴ:

• Let radius of the second circle ⇒ R cm.

ᴀ/ǫ,

• Area of the second circle ➝ Double the area of the first circle.

➠ πR² = 2 ༝ πr²

➠ R² = (2 ༝ πr²) ༝ π

➠ R² = 2 ༝ r²

➠ R = √2 ༝ r

➠ R = √2 ༝ 14

➠ R = 14√2 cm.

• Hence, Radius of Circle is 14√2 cm.