"Formula of a circle" is too vague to be meaningful. Perhaps you meant, "Formula for the area of a circle in terms of its circumference."
The area of a circle in terms of its radius is A = πr^2. To put this formula to use, we have to know the radius of the circle. The circumference of a circle in terms of its radius is C = 2πr, so a formula for the radius is r = C / (2π).
Now let's find a formula for the area of a circle in terms of its circumference:
C C^2
A = πr^2 = π { ---------------- }^2 = ------------
2π 4π
or:
A = (C^2) / 4π
Answer:
4$
Step-by-step explanation:
Let's say 1000 dollars was spent on all of these. That would mean 170 dollars and 240 were spent on food and entertainment respectivly. If we want to see how much of the total cost was spent on these things, we would have to add them and divide them by 1000, so:
Answer:
59/9
Step-by-step explanation:
d=100. 12/4=3 min/lap
12mins 4 laps. 100/180= 59/9
R=50
2(pie)(50)=100(pie)
Answer:
x ^2+
y^
2
=
25
Step-by-step explanation:
Square both sides:
r
^2
=
5^
2
Substitute x
^2
+
y^
2 for r
^2
:
x
^2+
y
^2
=
5
^2
Insert the center -0 into the x and y terms:
(
x
−
0
)^
2
+
(
y
−
0
)
^2
=
5
^2
This is the standard form for a circle whose center is (
0,
0
) and the radius is 5.
