Solve 1+r/R=A

$$1 + \frac { r } { R } = A$$

Solve for A

$$A=\frac{r+R}{R}$$

$$R\neq 0$$

Steps for Solving Linear Equation

Multiply both sides of the equation by R.

$$R+r=AR$$

Swap sides so that all variable terms are on the left hand side.

$$AR=R+r$$

The equation is in standard form.

$$RA=r+R$$

Divide both sides by R.

$$\frac{RA}{R}=\frac{r+R}{R}$$

Dividing by R undoes the multiplication by R.

$$A=\frac{r+R}{R}$$

Solve for R

$$\left\{\begin{matrix}R=-\frac{r}{1-A}\text{, }&r\neq 0\text{ and }A\neq 1\\R\neq 0\text{, }&A=1\text{ and }r=0\end{matrix}\right.$$

Steps for Solving Linear Equation

Variable R cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by R.

$$R+r=AR$$

Subtract AR from both sides.

$$R+r-AR=0$$

Subtract r from both sides. Anything subtracted from zero gives its negation.

$$R-AR=-r$$

Combine all terms containing R.

$$\left(1-A\right)R=-r$$

Divide both sides by 1-A.

$$\frac{\left(1-A\right)R}{1-A}=-\frac{r}{1-A}$$

Dividing by 1-A undoes the multiplication by 1-A.

$$R=-\frac{r}{1-A}$$

Variable R cannot be equal to 0.

$$R=-\frac{r}{1-A}\text{, }R\neq 0$$