Solve for a B=-D+1/7ua

$B = - D + \frac{1}{7} u a$

Rewrite the equation as $- D + \frac{1}{7} \cdot (u a) = B$ .

$- D + \frac{1}{7} \cdot (u a) = B$

Multiply $\frac{1}{7} (u a)$ .

Combine $u$ and $\frac{1}{7}$ .

$- D + \frac{u}{7} a = B$

Combine $\frac{u}{7}$ and $a$ .

$- D + \frac{u a}{7} = B$

Add $D$ to both sides of the equation.

$\frac{u a}{7} = B + D$

Multiply both sides of the equation by $7$ .

$7 \frac{u a}{7} = 7 (B + D)$

Simplify both sides of the equation.

Simplify the left side.

Cancel the common factor of $7$ .

Cancel the common factor.

$7 \frac{u a}{7} = 7 (B + D)$

Rewrite the expression.

$u a = 7 (B + D)$

Simplify the right side.

Apply the distributive property.

$u a = 7 B + 7 D$

Divide each term in $u a = 7 B + 7 D$ by $u$ and simplify.

Divide each term in $u a = 7 B + 7 D$ by $u$ .

$\frac{u a}{u} = \frac{7 B}{u} + \frac{7 D}{u}$

Simplify the left side.

Cancel the common factor of $u$ .

Cancel the common factor.

$\frac{u a}{u} = \frac{7 B}{u} + \frac{7 D}{u}$

Divide $a$ by $1$ .

$a = \frac{7 B}{u} + \frac{7 D}{u}$