In a circle, area and circumference can be found using the formulas A=(pi)r^2 and C=2(pi)r, respectively, Write a formula for A in terms of C.(your answer should not contain r)

Respuesta :

Answer:

[tex]A = \dfrac{C^2}{4\pi}[/tex]

Step-by-step explanation:

Given that

Area of a circle [tex]A=\pi r^2[/tex]

Circumference of the circle [tex]C = 2 \pi r[/tex]

Let us re-write the equation of area of circle:

[tex]A=\pi r^2[/tex]

[tex]A = \pi \times r \times r[/tex]

Multiplying and dividing with 2:

[tex]A = \dfrac{2\pi r}{2} \times r\\\text{Putting }2\pi r = C:\\\Rightarrow A = \dfrac{C}{2} \times r\\\text{Multiplying and dividing by } 2\pi:\\\Rightarrow A = \dfrac{C}{2} \times \dfrac{2\pi r}{2\pi}\\\text{Putting }2\pi r = C:\\\Rightarrow A = \dfrac{C \times C}{4 \pi}\\\Rightarrow A = \dfrac{C^2}{4 \pi}[/tex]

Hence, A in terms of C can be represented as:

[tex]A = \dfrac{C^2}{4\pi}[/tex]

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