Given the following formula, solve for r. C=2πr A. r=2πC B. r=(C−π)/2 C. r=C/2π D. r=C−2π

Question
Circles
asked 2021-01-19
Given the following formula, solve for r. \(\displaystyle{C}={2}π{r}\)
A. \(\displaystyle{r}={2}π{C}\)
B. \(\displaystyle{r}=\frac{{{C}−π}}{{2}}\)
C. \(\displaystyle{r}=\frac{{C}}{{2}}π\)
D. \(\displaystyle{r}={C}−{2}π\)

Answers (1)

2021-01-20
To solve an equation, we need to use inverse operations.
For \(\displaystyle{C}={2}π{r}\), the rr is being multiplied by 2π. To solve for r we would then need to divide both sides by 2π since division is the inverse operation of multiplication.
Dividing both sides of C=2πr by 2π gives \(\displaystyle\frac{{C}}{{2}}π={2}π\frac{{r}}{{2}}π.\)
Simplifying then gives C. \(\displaystyle{r}=\frac{{C}}{{2}}π.\)
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