.Which formula correctly describes the proportional relationship between the circumference of a circle and the diameter?(1 point)

Responses

π=dC
pi equals Start Fraction d over upper C

A=πr2
upper A equals pi r squared

C=πd
upper C equals Start Fraction pi over d End Fraction

Cd=π

5 answers

C=πd
Use the correct formula to find the area of a circle if the diameter is 21 mi. Round to the nearest hundredths place. Use 3.14 for π .(1 point)
Responses

346.19 mi.2
346.19 mi squared

131.88 mi.2
131.88 mi squared

65.94 mi.2
65.94 mi squared

1,384.74 mi.2
To find the area of a circle, we use the formula A=πr^2, where r is the radius and d is the diameter.

Given that the diameter is 21 mi, so the radius (r) would be half of that, which is 21/2 = 10.5 mi.

Now, plug in the values into the formula:

A = π(10.5)^2
A = π(110.25)
A ≈ 346.19 mi^2

So, the correct answer is 346.19 mi^2.
Which of the following is the correct formula for finding the area of a circle?(1 point)
Responses

A=πr2
upper A equals pi r squared

A=πd
upper A equals pi d

A=2πr
upper A equals 2 pi r

A=C2÷4πA=πd2
A=πr^2
(upper A equals pi r squared)