Solve {l}{x=-3}{y=4}{z=x+{(y-x)}+xy}{text{Solvefor}atext{where}}{a=z}

$$\left. \begin{array} { l } { x = -3 }\\ { y = 4 }\\ { z = x + {(y - x)} + x y }\\ { \text{Solve for } a \text{ where} } \\ { a = z } \end{array} \right.$$

Solve for x, y, z, a

$$a=-8$$

Solution Steps

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

$$z=-3+4-\left(-3\right)-3\times 4$$

Do the multiplications.

$$z=-3+4+3-12$$

Add -3 and 4 to get 1.

$$z=1+3-12$$

Add 1 and 3 to get 4.

$$z=4-12$$

Subtract 12 from 4 to get -8.

$$z=-8$$

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

$$a=-8$$

The system is now solved.

$$x=-3 y=4 z=-8 a=-8$$