Solve {l}{f+5=-10}{14=9+5u}{9=10n+9}

$$\left. \begin{array} { l } { f + 5 = - 10 } \\ { 14 = 9 + 5 u } \\ { 9 = 10 n + 9 } \end{array} \right.$$

Solve for f, u, n

$$f=-15$$

$$u=1$$

$$n=0$$

Solution Steps

Consider the first equation. Subtract 5 from both sides.

$$f=-10-5$$

Subtract 5 from -10 to get -15.

$$f=-15$$

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

$$9+5u=14$$

Subtract 9 from both sides.

$$5u=14-9$$

Subtract 9 from 14 to get 5.

$$5u=5$$

Divide both sides by 5.

$$u=\frac{5}{5}$$

Divide 5 by 5 to get 1.

$$u=1$$

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

$$10n+9=9$$

Subtract 9 from both sides.

$$10n=9-9$$

Subtract 9 from 9 to get 0.

$$10n=0$$

Divide both sides by 10. Zero divided by any non-zero number gives zero.

$$n=0$$

The system is now solved.

$$f=-15 u=1 n=0$$