Solve {l}{4x-12+3=3x-27}{y=3x-27}{text{Solvefor}ztext{where}}{z=y}

$$\left. \begin{array} { l } { 4 x - 12 + 3 = 3 x - 27 }\\ { y = 3 x - 27 }\\ { \text{Solve for } z \text{ where} } \\ { z = y } \end{array} \right.$$

Solve for x, y, z

$$z=-81$$

Solution Steps

Consider the first equation. Add -12 and 3 to get -9.

$$4x-9=3x-27$$

Subtract 3x from both sides.

$$4x-9-3x=-27$$

Combine 4x and -3x to get x.

$$x-9=-27$$

Add 9 to both sides.

$$x=-27+9$$

Add -27 and 9 to get -18.

$$x=-18$$

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

$$y=3\left(-18\right)-27$$

Multiply 3 and -18 to get -54.

$$y=-54-27$$

Subtract 27 from -54 to get -81.

$$y=-81$$

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

$$z=-81$$

The system is now solved.

$$x=-18 y=-81 z=-81$$