Select the correct answer.

Given the following formula, solve for [tex]r[/tex].
[tex]
C=2 \pi r
[/tex]

A. [tex]r=\frac{C}{2 \pi}[/tex]

B. [tex]r=\frac{C-\pi}{2}[/tex]

C. [tex]r=2 \pi C[/tex]

D. [tex]r=C-2 \pi[/tex]



Answer :

To solve for [tex]\( r \)[/tex] in the given formula:

[tex]\[ C = 2 \pi r \][/tex]

we need to isolate [tex]\( r \)[/tex].

1. Start with the given formula:
[tex]\[ C = 2 \pi r \][/tex]

2. Divide both sides of the equation by [tex]\( 2 \pi \)[/tex]:
[tex]\[ \frac{C}{2 \pi} = r \][/tex]

3. Simplify the right-side:
[tex]\[ r = \frac{C}{2 \pi} \][/tex]

So, the correct expression for [tex]\( r \)[/tex] in terms of [tex]\( C \)[/tex] is:

[tex]\[ r = \frac{C}{2 \pi} \][/tex]

Now, let's match this expression with the given choices:

A. [tex]\( r = \frac{C}{2 \pi} \)[/tex] - This is correct.

B. [tex]\( r = \frac{C - \pi}{2} \)[/tex] - This is incorrect because it does not effectively isolate [tex]\( r \)[/tex] according to the given formula.

C. [tex]\( r = 2 \pi C \)[/tex] - This is incorrect because it multiplies [tex]\( C \)[/tex] by [tex]\( 2 \pi \)[/tex] instead of dividing by [tex]\( 2 \pi \)[/tex].

D. [tex]\( r = C - 2 \pi \)[/tex] - This is incorrect because it subtracts instead of dividing by [tex]\( 2 \pi \)[/tex].

Thus, the correct choice is:

[tex]\[ \boxed{1} \][/tex]

So, you should select:

A. [tex]\( r = \frac{C}{2 \pi} \)[/tex]

Answer:

A. [tex]r=\frac{C}{2\pi}[/tex]

Step-by-step explanation:

C = 2πr (Starting equation)

C/(2π) = r (Divide both sides by 2π)