Answer:
To find the area of a circle you use the formula 
r is the radius so plug that in.
if you only have the diameter, just divide that number by 2 to get the radius
Answer:
The most likely solution sought is 13:
Beginning with 3: subtract 9, add 18, subtract 8, add 16, subtract 7, add 14, etc. Each time, reduce the number subtracted by one, and double that number to add.
So, beginning with 3: 3-9 = -6, -6+2(9) = 12, 12-8 = 4, 4+2(8) = 20, 20-7 = 13, etc.
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Step-by-step explanation:
Answer:
(-2,-1)
Step-by-step explanation:
To reflect something across an axis we need to change the coordinate of the other axis. To reflect a point across the X axis we need to change the sign on the Y axis because that will put it on the other side of the X axis. In this question the 1 is what we will change from positive to negative. By doing this it will move the point from above the X axis to below the X axis.
I hope this helps and please don't hesitate to ask if there is anything still unclear!
Email the teacher and see if she can check it at a later time