Answer:

Step-by-step explanation:
I am assuming that you are asking what is [x] - 5 if f(86).
When you have this kind of question, what you do is to substitute the variable inside the parenthesis, so like what is says, f(x). If the question replaces the variable x with 86, that means you input the number into the equation.
So [x] - 5, if f(86).
Substitute:
86 - 5

Answer:
D
Step-by-step explanation:
The area of a circle can be found using:
a=πr^2
We know that the radius is 10 meters. Therefore, we can substitute 10 in for r.
a=π*10^2
Evaluate the exponent
a=π*100
Multiply pi and 100
a=314.159265359
Round to the nearest tenth: there is a 5 in the hundreth place, which indicates we round up the 1 in the tenths place to a 2.
a=314.2
The area is 314.2 square meters, or choice D
Answer:
1, -3, -5, -7, -11, -13, -15, -17?
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