Solve by Factoring (4k+5)(k+1)=0

$(4 k + 5) (k + 1) = 0$

Step 1

If any individual factor on the left side of the equation is equal to $0$ , the entire expression will be equal to $0$ .

$4 k + 5 = 0$

$k + 1 = 0$

Step 2

Set $4 k + 5$ equal to $0$ and solve for $k$ .

Set $4 k + 5$ equal to $0$ .

$4 k + 5 = 0$

Solve $4 k + 5 = 0$ for $k$ .

Subtract $5$ from both sides of the equation.

$4 k = - 5$

Divide each term in $4 k = - 5$ by $4$ and simplify.

Divide each term in $4 k = - 5$ by $4$ .

$\frac{4 k}{4} = \frac{- 5}{4}$

Simplify the left side.

Cancel the common factor of $4$ .

Cancel the common factor.

$\frac{4 k}{4} = \frac{- 5}{4}$

Divide $k$ by $1$ .

$k = \frac{- 5}{4}$

Simplify the right side.

Move the negative in front of the fraction.

$k = - \frac{5}{4}$

Step 3

Set $k + 1$ equal to $0$ and solve for $k$ .

Set $k + 1$ equal to $0$ .

$k + 1 = 0$

Subtract $1$ from both sides of the equation.

$k = - 1$

Step 4

The final solution is all the values that make $(4 k + 5) (k + 1) = 0$ true.

$k = - \frac{5}{4}, - 1$