Answer:
perimeter = (18 +9π) cm
area = (81 -20.25π) cm^2
Step-by-step explanation:
The perimeter of the shaded area is the circumference of the circle added to two sides of the square. The circumference of the circle is π times the diameter, so the perimeter is ...
p = 2(9 cm) + π(9 cm) = (18 +9π) cm
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The area of the shaded portion is the difference between the area of the square and the area of the circle. The area of the square is the square of the diameter. The area of the circle is π/4 times that value.
A = (9 cm^2) + (π/4)(9 cm^2) = (81 +20.25π) cm^2
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Comment on circle area
The formula you often see is ...
A = πr^2 . . . . r is the radius
since r = d/2, where d is the diameter, this can also be written as ...
A = π(d/2)^2 = (π/4)d^2
Here, the diameter of the circle is the same as the side length of its enclosing square, so the area of the circle is π/4 times the area of the enclosing square.
The answer is B. 5P5 x 20P15.
This is because to make the second grade students to sit in the first row we have 5 seats and 5 students so we will permute the 5 students to those 5 seats. So 5P5.
Now we are left with 20 seats and 15 first grade students so we can simply permute those 15 students into those 20 seats. So 20P15.
Finally using the counting rule principle we will multiply both of these so 5P5 x 20P15.
Answer:
22
Step-by-step explanation:
I would assume that the 6% rate would carry for the rest of the year, i.e. all 365 days, 6% of those have clouds interfering with stargazing
365 * 6% = 365 * 0.06 = 21.9, and round up to 22 because you can't really have .9 of a day here.
Answer:
7
3
all real numbers
y>0
Step-by-step explanation:
Just got it right on edge. i got you little bro