Answer:
1. diameter=5.54m
2. radius=9.55cm
3. area=11.46feet²
Step-by-step explanation:
1. The formula of the area of a circle is: A=[tex]\pi r^{2}[/tex]
A: area of the circle=25m²
[tex]\pi[/tex] : Pi≈3.14
r: radius of the circle= unknown
Solve the equation to find r:
25=(3.14)r²
r²=[tex]\frac{25}{3.14}[/tex] =7.69m²
r= √7.69= 2.77m
diameter d= 2 x r =2 x 2.77 =5.54m
2. The formula of the perimeter of a circle is: P=2[tex]\pi r[/tex]
P: perimeter of the circle= 30cm
[tex]\pi[/tex] : Pi≈3.14
r: radius of the circle= unknown
Solve the equation to find r:
30=(3.14)r
r= [tex]\frac{30}{3.14}[/tex] = 9.55cm
radius r = 9.55cm
3. First we have to find r (radius) from the equation of perimeter:
P=2[tex]\pi r[/tex]
r= [tex]\frac{P}{2\pi }[/tex] = [tex]\frac{12}{2(3.14)}[/tex] = [tex]\frac{12}{6.28}[/tex] =1.91 feet
Substitute r in the equation of area to get the area:
A= [tex]\pi r^{2}[/tex] = 3.14 (1.91)² = 3.14(3.65) = 11.46 feet²
