Question

Solve the equation. Check your solution.

$\mathbf{-}\mathbf{9}\mathbf{z}\mathbf{+}\mathbf{4}\mathbf{=}\mathbf{-}\mathbf{5}$

Short answer

The solution for the equation $-9z+4=-5$ is $z=1$.

Step-by-step solution

.  Separate the variable and constants

Write the original equation and separate the variables.

$\begin{array}{c}-9z+4=-5\\ -9z=-5-4\\ -9z=-9\end{array}$

Step 2.  Solve for z

Now, divide both sides of the equation by -9.

$\begin{array}{c}\frac{-9z}{-9}=\frac{-9}{-9}\\ z=1\end{array}$

Therefore, the solution of the equation is$z=1$.

Step 3.  Check the solution 

To check the solution, write the original equation and substitute the value of $z$.

$-9z+4=-5$

Now, substitute $z=1$and check the result.

$\begin{array}{c}-9\left(1\right)+4=-5\\ -9+4=-5\\ -5=-5\end{array}$

As the left-hand side is equal to right hand side, this signifies that the solution is correct.