Solve {l}{4y=77}{z=3y+20}{text{Solvefor}atext{where}}{a=z}

$$\left. \begin{array} { l } { 4 y = 77 }\\ { z = 3 y + 20 }\\ { \text{Solve for } a \text{ where} } \\ { a = z } \end{array} \right.$$

Solve for y, z, a

$$a = \frac{311}{4} = 77\frac{3}{4} = 77.75$$

Solution Steps

Consider the first equation. Divide both sides by 4.

$$y=\frac{77}{4}$$

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

$$z=3\times \frac{77}{4}+20$$

Multiply 3 and \frac{77}{4} to get \frac{231}{4}.

$$z=\frac{231}{4}+20$$

Add \frac{231}{4} and 20 to get \frac{311}{4}.

$$z=\frac{311}{4}$$

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

$$a=\frac{311}{4}$$

The system is now solved.

$$y=\frac{77}{4} z=\frac{311}{4} a=\frac{311}{4}$$