Answer:
[-8,8]
Step-by-step explanation:
domain is the set of x values that the graph covers
This graph starts at -8 and ends at 8 (including those points and all points between them).
That makes the domain [-8,8]

can also be written as 2i
where i = √-1

Rationalizing denominator,
Answer:
9
Step-by-step explanation:
Compare your x2 + y2=81 to the following:
x^2 + y^2 = 81
The " ^ " symbol indicates exponentiation.
Now compare x^2 + y^2 = 81 to
x^2 + y^2 = r^2.
This is the standard equation of a circle of radius r centered at the origin, (0,0). You can see for yourself that 81 must equal r^2.
Taking the square root of 81, we get plus or minus 9.
But the radius must be positive, so we reject the -9 and take +9.
The radius is 9.
Step 1) Draw a line from point F to point S. A rectangle forms (rectangle FSCW)
Step 2) Find the area of this rectangle. The area is 18 square units because it is 2 units high and 9 units across (9*2 = 18). You can count out the spaces or you can note how we go from x = -4 to x = 5 so subtracting the values gives -4-5 = -9 which has an absolute value of 9.
Step 3) Find the area of triangle FSN. The base is 9 units and the height is 6 units (count out the spaces or subtract y values). So the area is A = b*h/2 = 9*6/2 = 54/2 = 27
Step 4) Add up the area of the rectangle to the area of the triangle: 18+27 = 45
Final Answer: 45 square units
note: another way to find the answer is to find the area of rectangle WABC where point A is at (-4,4) and point B is at (5,4). Then subtract off the triangular areas of AFN and BNS
A=πr2=π·92≈254.469
your answer is 254.469