Solve {l}{4x-5=0}{y=7x+1}{text{Solvefor}ztext{where}}{z=y}

$$\left. \begin{array} { l } { 4 x - 5 = 0 }\\ { y = 7 x + 1 }\\ { \text{Solve for } z \text{ where} } \\ { z = y } \end{array} \right.$$

Solve for x, y, z

$$z = \frac{39}{4} = 9\frac{3}{4} = 9.75$$

Solution Steps

Consider the first equation. Add 5 to both sides. Anything plus zero gives itself.

$$4x=5$$

Divide both sides by 4.

$$x=\frac{5}{4}$$

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

$$y=7\times \frac{5}{4}+1$$

Multiply 7 and \frac{5}{4} to get \frac{35}{4}.

$$y=\frac{35}{4}+1$$

Add \frac{35}{4} and 1 to get \frac{39}{4}.

$$y=\frac{39}{4}$$

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

$$z=\frac{39}{4}$$

The system is now solved.

$$x=\frac{5}{4} y=\frac{39}{4} z=\frac{39}{4}$$