Solve {l}{5x+4-2x=87}{y=x-8}{text{Solvefor}ztext{where}}{z=y}

$$\left. \begin{array} { l } { 5 x + 4 - 2 x = 87 }\\ { y = x - 8 }\\ { \text{Solve for } z \text{ where} } \\ { z = y } \end{array} \right.$$

Solve for x, y, z

$$z = \frac{59}{3} = 19\frac{2}{3} \approx 19.666666667$$

Solution Steps

Consider the first equation. Combine 5x and -2x to get 3x.

$$3x+4=87$$

Subtract 4 from both sides.

$$3x=87-4$$

Subtract 4 from 87 to get 83.

$$3x=83$$

Divide both sides by 3.

$$x=\frac{83}{3}$$

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

$$y=\frac{83}{3}-8$$

Subtract 8 from \frac{83}{3} to get \frac{59}{3}.

$$y=\frac{59}{3}$$

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

$$z=\frac{59}{3}$$

The system is now solved.

$$x=\frac{83}{3} y=\frac{59}{3} z=\frac{59}{3}$$