Solve {l}{-8=4x/5}{y=-2-x}{text{Solvefor}ztext{where}}{z=y}

$$\left. \begin{array} { l } { -8 = \frac{4 x}{5} }\\ { y = -2 - x }\\ { \text{Solve for } z \text{ where} } \\ { z = y } \end{array} \right.$$

Solve for x, y, z

$$z=8$$

Solution Steps

Consider the first equation. Multiply both sides by 5.

$$-8\times 5=4x$$

Multiply -8 and 5 to get -40.

$$-40=4x$$

Swap sides so that all variable terms are on the left hand side.

$$4x=-40$$

Divide both sides by 4.

$$x=\frac{-40}{4}$$

Divide -40 by 4 to get -10.

$$x=-10$$

Consider the second equation. Insert the known values of variables into the equation.

$$y=-2-\left(-10\right)$$

Multiply -1 and -10 to get 10.

$$y=-2+10$$

Add -2 and 10 to get 8.

$$y=8$$

Consider the third equation. Insert the known values of variables into the equation.

$$z=8$$

The system is now solved.

$$x=-10 y=8 z=8$$