Solve for d dx+3x=12

$d x + 3 x = 12$

Step 1

Subtract $3 x$ from both sides of the equation.

$d x = 12 - 3 x$

Step 2

Divide each term in $d x = 12 - 3 x$ by $x$ and simplify.

Divide each term in $d x = 12 - 3 x$ by $x$ .

$\frac{d x}{x} = \frac{12}{x} + \frac{- 3 x}{x}$

Simplify the left side.

Cancel the common factor of $x$ .

Cancel the common factor.

$\frac{d x}{x} = \frac{12}{x} + \frac{- 3 x}{x}$

Divide $d$ by $1$ .

$d = \frac{12}{x} + \frac{- 3 x}{x}$

Simplify the right side.

Cancel the common factor of $x$ .

Cancel the common factor.

$d = \frac{12}{x} + \frac{- 3 x}{x}$

Divide $- 3$ by $1$ .

$d = \frac{12}{x} - 3$