Answered

the area of a circle is 28pi cm^2. find the area of a circle with a radius half the length of the original circle.

Answer :

Answer:

The area of circle with radius half of original circle is 7 π  cm² .

Step-by-step explanation:

Given as :

The Area of original circle = 28 π square centimeter

Let The radius of original circle  = R

Let The area of circle with radius half of original circle = A square centimeters

Let The radius of circle with radius half of original circle = R'

Now, According to question

Area of original circle =  π × radius²

So, 28 π cm² = π × R²

Or, R² = [tex]\frac{28\times \Pi }{\Pi }[/tex]

Or, R² = 28 cm²

∴  R = [tex]\sqrt{28}[/tex] cm

i.e R = 2 [tex]\sqrt{7}[/tex] cm

So, The radius of original circle = R =  2 [tex]\sqrt{7}[/tex] cm

Again

∵ The radius of circle with radius half of original circle = R'

So, R' = [tex]\dfrac{R}{2}[/tex]

i.e  R' = [tex]\frac{2\sqrt{7}}{2}[/tex]

∴  R' =  [tex]\sqrt{7}[/tex] cm

So, The area of circle with radius half of original circle =  π × R'²

i.e A = π × R'²

Or, A = π ×([tex]\sqrt{7}[/tex]) ²

or, A =  π × 7

So, The area of circle with radius half of original circle = 7 π  cm²

Hence The area of circle with radius half of original circle is 7 π  cm² . Answer