Answer: A; r = square root (S/4pi)
Step-by-step explanation:
1. Divide 4pi on both sides to get r^2 by itself so the left side becomes S/4pi (you do this because 4, pi, and r^2 are being multiplied together on the right side in the original equation so to cancel that out and get r by itself you do the opposite of multiplication)
The equation should now look like r^2 = S/4pi
2. Square root both sides including r to get rid of the r^2 so it becomes just r (also when you square root both sides, you square root all of S/4pi not just S or 4pi but the whole thing)
After you do that, you get r = square root (S/4pi) which is answer A
Hope this helps! :)
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Answer:</h3>
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Step-by-step explanation:</h3>
If the trapezoid is isosceles, angles A and C are supplementary, so ...
... (4x+4) +(7x+11) = 180
... 11x +15 = 180 . . . . . . collect terms
... 11x = 165 . . . . . . . . . subtract 15
... x = 15 . . . . . . . . . . . . divide by the coefficient of x
And angles C and E are congruent.
... 4·15 +4 = 21y +1
... 63 = 21y . . . . . subtract 1
... 3 = y . . . . . . . . divide by the coefficient of y
This solution to this problem is predicated on the fact that the circumference is just:
. A straight line going through the center of the garden would actually be the diameter, which is well known to be two times the radius of the circle, so we can say that the circumference is just:

So, solving for both the radius and the diameter gives us:

So, the length of thes traight path that goes through the center of the guardain is just
, and we can use the radius for the next part of the problem.
The area of a circle is
, which means we can just plug in the radius and find our area:

So, we have found our area(
) and the problem is done.
Answer: Complex
Step-by-step explanation: