Answer:
225π cm^2, 706.5 cm^2, 706.858... cm^2
Step-by-step explanation:
The area of a circle can be found using the following equation:
[tex]a=\pi r^2[/tex]
We know the radius is 15 cm, so we can substitute 15 cm in for r.
[tex]a=\pi (15cm)^2[/tex]
1. In terms of pi
To find the area in terms of pi, evaluate everything possible without multiplying by pi.
Evaluate the exponent.
[tex]a=\pi (15cm)^2[/tex]
15cm^2= 15 cm * 15 cm = 225 cm^2
[tex]a=\pi * 225 cm^2[/tex]
This can be rewritten as:
[tex]a=225\pi cm^2[/tex]
2. Using 3.14 for pi
Substitute 3.14 in for pi.
[tex]a=\pi (15cm)^2[/tex]
[tex]a=3.14*(15cm)^2[/tex]
[tex]a=3.14*225 cm^2[/tex]
Multiply
[tex]a=706.5 cm^2[/tex]
3. Using 3.14159265.... as pi
[tex]a=\pi (15cm)^2[/tex]
[tex]a=\pi *225 cm^2[/tex]
Multiply, using the pi button on a calculator
[tex]a=706.858346 cm^2[/tex]
