Solve for a -Da+h^2=na

$- D a + h^{2} = n a$

Step 1

Subtract $n a$ from both sides of the equation.

$- D a + h^{2} - n a = 0$

Step 2

Subtract $h^{2}$ from both sides of the equation.

$- D a - n a = - h^{2}$

Step 3

Factor $a$ out of $- D a - n a$ .

Factor $a$ out of $- D a$ .

$a (- D) - n a = - h^{2}$

Factor $a$ out of $- n a$ .

$a (- D) + a (- n) = - h^{2}$

Factor $a$ out of $a (- D) + a (- n)$ .

$a (- D - n) = - h^{2}$

Step 4

Divide each term in $a (- D - n) = - h^{2}$ by $- D - n$ and simplify.

Divide each term in $a (- D - n) = - h^{2}$ by $- D - n$ .

$\frac{a (- D - n)}{- D - n} = \frac{- h^{2}}{- D - n}$

Simplify the left side.

Cancel the common factor of $- D - n$ .

Cancel the common factor.

$\frac{a (- D - n)}{- D - n} = \frac{- h^{2}}{- D - n}$

Divide $a$ by $1$ .

$a = \frac{- h^{2}}{- D - n}$

Simplify the right side.

Move the negative in front of the fraction.

$a = - \frac{h^{2}}{- D - n}$

Factor $- 1$ out of $- D$ .

$a = - \frac{h^{2}}{- (D) - n}$

Factor $- 1$ out of $- n$ .

$a = - \frac{h^{2}}{- (D) - (n)}$

Factor $- 1$ out of $- (D) - (n)$ .

$a = - \frac{h^{2}}{- (D + n)}$

Simplify the expression.

Rewrite $- (D + n)$ as $- 1 (D + n)$ .

$a = - \frac{h^{2}}{- 1 (D + n)}$

Move the negative in front of the fraction.

$a = - - \frac{h^{2}}{D + n}$

Multiply $- 1$ by $- 1$ .

$a = 1 \frac{h^{2}}{D + n}$

Multiply $\frac{h^{2}}{D + n}$ by $1$ .

$a = \frac{h^{2}}{D + n}$