Answer:
Area of shaded region ≈ 192.42
Step-by-step explanation:
21/2 = radius
radius = 10.5 m
A = πr squared
Area of shaded region≈346.36
10.5 - 3.5 = 7
Area of unshaded region ≈ 153.94
346.36 - 153.94 = 192.42
Yes, number 20 is dividing.
Yes, number 21 is multiplying.
You have a lot of questions here, try breaking them up into multiple posts and you may get more responses.
I will help with some.
<span>(x+3)=0
The solution is just -3.
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3m(m-4)=0
The two solutions are 0 and 4.
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(r-3)(r+2)=0
The two solutions are and 3 and -2.
</span>
I hope this gets you started in the right direction.