To determine the area if the circle, you must know the diameter or the radius of a circle.
If you know the radius of a circle, use this as your formula. Remember: Pi (the greek symbol thingy) is equal to 3.1415. (A is equal to area of the circle and r represents the radius)

If you know the diameter, just divide the diameter to get the radius then use the same equation.
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Answer:
(-7, 3) i think, not 100% sure
Step-by-step explanation:
Answer:
b=7
Step-by-step explanation: