Formula of area of circle and the circumference

A= πr2

Step-by-step explanation:

The area of circle can be calculated by using the formulas: Area = π x r2, in terms of radius 'r'. Area = (π/4) x d2, in terms of diameter, 'd'. Area = C2/4π, in terms of circumference, 'C'.

the answer is b: 18

step-by-step explanation:

use the pythagorean theorem to .

a^2+b^2=c^2

plug 18 for "r"

the 2 legs are 18 and 24

18^2+24^2=c^2

324+576=c^2

900=c^2

c=30

30-12=18

18 is the radius

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