Question

a. Diameter, d = 2rd = 2r The formula using function notation is ; The value when r = 5r = 5 is ; The diameter of the circle is feet when the radius is feet. b. Area, A = πr2A = πr2 The formula using function notation is ; The value when r = 5r = 5 is ; The area of the circle is feet when the radius is feet. c. Circumference C = 2πrC = 2πr The formula using function notation is ; The value when r = 5r = 5 is ; The circumference of the circle is feet when the radius is feet.

Answer 1

Answer with explanation:

Given : The diameter of the circle = 2r , where r is the radius.

Function notation for diameter :
`D(r)=2r`

If the value of r= 5 feet

Then , the diameter of the circle is feet = 2(5) feet = 10 feet

Hence, the diameter of the circle is 10 feet when the radius is 5 feet.

Also, area of circle :
`A=\pi r^2` , where r is the radius .

Function notation for area :
`A(r)=\pi r^2`

For r= 5 feet

`A(r)=\pi (5)^2`

`\Rightarrow\ A(r)=25\pi\text{ square feet}`

Hence, The area of the circle is
`25\pi` square feet when the radius is 5 feet.

Also, the circumference of circle =
`2\pi r`

Function notation for circumference =
`C(r)=2\pi r`

For r= 5 feet

`C(r)=2\pi (5)=10\pi \text{ feet}`

Hence, The circumference of the circle is
`10\pi` feet when the radius is feet.