please explain how to do this
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Answer:
Option 4
Step-by-step explanation:
Area of a circle (A) = πr²-------------(i)
Circumference (C) = 2πr
=>C = 2πr
=> 2πr= C
=> π = C/2r
Substituting the value of π = C/2r in the first equation i.e (i)
A = (C×r²)/2r
= (C . r)/2
= 1/2 × C × r
Therefore, option 4 is the correct option