Which of the following expressions correctly shows the relationship between the circumference and the area of a circle?(1 point)
Responses
Cd=π
Start Fraction upper C over d End Fraction equals pi
C2=4πA
upper C squared equals 4 pi upper A
A=πr2
upper A equals pi r squared
C=2πr
C=2πr
If C=12π , what is the area of the circle? (1 point)
Responses
144π
144 pi
36π
36 pi
12π
12 pi
24π
If C=12π, we use the formula: C = 2πr, where r is the radius of the circle. Given C = 12π, we can solve for r:
12π = 2πr
r = 6 units
Then, we calculate the area using the formula A = πr^2:
A = π(6)^2
A = 36π
Therefore, the area of the circle would be 36π. So the correct answer is: 36π.
Which formula is used to find the area of a circle when given the radius?(1 point)
Responses
A=d2
upper A equals d squared
A=r
upper A equals r
A=2r
upper A equals 2 r
A=r2
A=r²
Which formula is used to find the circumference of a circle when the radius is given?(1 point)
Responses
C=2d
upper C equals 2 d
C=2r
upper C equals 2 r
C=r2
upper C equals r squared
C=r