Solve {l}{12000=20x+15*350}{text{Solvefor}ytext{where}}{y=10{(800-4x)}}

$$\left. \begin{array} { l } { 12000 = 20 x + 15 \cdot 350 }\\ { \text{Solve for } y \text{ where} } \\ { y = 10 {(800 - 4 x)} } \end{array} \right.$$

Solve for x, y

$$y=-5500$$

Solution Steps

Consider the first equation. Multiply 15 and 350 to get 5250.

$$12000=20x+5250$$

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

$$20x+5250=12000$$

Subtract 5250 from both sides.

$$20x=12000-5250$$

Subtract 5250 from 12000 to get 6750.

$$20x=6750$$

Divide both sides by 20.

$$x=\frac{6750}{20}$$

Reduce the fraction \frac{6750}{20} to lowest terms by extracting and canceling out 10.

$$x=\frac{675}{2}$$

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

$$y=10\left(800-4\times \frac{675}{2}\right)$$

Multiply -4 and \frac{675}{2} to get -1350.

$$y=10\left(800-1350\right)$$

Subtract 1350 from 800 to get -550.

$$y=10\left(-550\right)$$

Multiply 10 and -550 to get -5500.

$$y=-5500$$

The system is now solved.

$$x=\frac{675}{2} y=-5500$$