Solve {l}{u=-4}{v=-5}{t=4}{s=frac{{(u+v)}t}{2}}{w=s}{x=w}{y=x}{z=y}{text{Solvefor}atext{where}}{a=z}

$$\left. \begin{array} { l } { u = -4 }\\ { v = -5 }\\ { t = 4 }\\ { s = \frac{{(u + v)} t}{2} }\\ { w = s }\\ { x = w }\\ { y = x }\\ { z = y }\\ { \text{Solve for } a \text{ where} } \\ { a = z } \end{array} \right.$$

Solve for u, v, t, s, w, x, y, z, a

$$a=-18$$

Solution Steps

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

$$s=\frac{\left(-4-5\right)\times 4}{2}$$

Subtract 5 from -4 to get -9.

$$s=\frac{-9\times 4}{2}$$

Multiply -9 and 4 to get -36.

$$s=\frac{-36}{2}$$

Divide -36 by 2 to get -18.

$$s=-18$$

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

$$w=-18$$

Consider the equation (6). Insert the known values of variables into the equation.

$$x=-18$$

Consider the equation (7). Insert the known values of variables into the equation.

$$y=-18$$

Consider the equation (8). Insert the known values of variables into the equation.

$$z=-18$$

Consider the equation (9). Insert the known values of variables into the equation.

$$a=-18$$

The system is now solved.

$$u=-4 v=-5 t=4 s=-18 w=-18 x=-18 y=-18 z=-18 a=-18$$