Solve {l}{7{(6-8*5x)}=220}{y=5}{text{Solvefor}ztext{where}}{z=y}

$$\left. \begin{array} { l } { 7 {(6 - 8 \cdot 5 x)} = 220 }\\ { y = 5 }\\ { \text{Solve for } z \text{ where} } \\ { z = y } \end{array} \right.$$

Solve for x, y, z

$$z=5$$

Solution Steps

Consider the first equation. Divide both sides by 7.

$$6-8\times 5x=\frac{220}{7}$$

Multiply 8 and 5 to get 40.

$$6-40x=\frac{220}{7}$$

Subtract 6 from both sides.

$$-40x=\frac{220}{7}-6$$

Subtract 6 from \frac{220}{7} to get \frac{178}{7}.

$$-40x=\frac{178}{7}$$

Divide both sides by -40.

$$x=\frac{\frac{178}{7}}{-40}$$

Express \frac{\frac{178}{7}}{-40} as a single fraction.

$$x=\frac{178}{7\left(-40\right)}$$

Multiply 7 and -40 to get -280.

$$x=\frac{178}{-280}$$

Reduce the fraction \frac{178}{-280} to lowest terms by extracting and canceling out 2.

$$x=-\frac{89}{140}$$

The system is now solved.

$$x=-\frac{89}{140} y=5 z=5$$