Solve for w -6y^2-21=s(y^2+w)

$- 6 y^{2} - 21 = s (y^{2} + w)$

Rewrite the equation as $s (y^{2} + w) = - 6 y^{2} - 21$ .

$s (y^{2} + w) = - 6 y^{2} - 21$

Divide each term in $s (y^{2} + w) = - 6 y^{2} - 21$ by $s$ and simplify.

Divide each term in $s (y^{2} + w) = - 6 y^{2} - 21$ by $s$ .

$\frac{s (y^{2} + w)}{s} = \frac{- 6 y^{2}}{s} + \frac{- 21}{s}$

Simplify the left side.

Cancel the common factor of $s$ .

Cancel the common factor.

$\frac{s (y^{2} + w)}{s} = \frac{- 6 y^{2}}{s} + \frac{- 21}{s}$

Divide $y^{2} + w$ by $1$ .

$y^{2} + w = \frac{- 6 y^{2}}{s} + \frac{- 21}{s}$

Simplify the right side.

Simplify each term.

Move the negative in front of the fraction.

$y^{2} + w = - \frac{(6) y^{2}}{s} + \frac{- 21}{s}$

Move the negative in front of the fraction.

$y^{2} + w = - \frac{6 y^{2}}{s} - \frac{21}{s}$

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

$w = - \frac{6 y^{2}}{s} - \frac{21}{s} - y^{2}$