$\"\"$

The equation is $\"\"$ .

Solve the equation $\"\"$ for z.

Apply distributive property : $\"\"$ .

$\"\"$

Subtract 10 from each side.

$\"\"$

$\"\"$ . $\"\"$

Divide each side by 20.

$\"\"$

Cancel common terms.

$\"\"$ . $\"\"$

To check the solution, substitute the value of $\"\"$ in the original equation.

$\"\"$

$\"\"$ .

The above statement is true, so the value of $\"\"$ is the solution of original equation. $\"\"$

The value of $\"\"$ .