Solve {l}{3x+y=5}{5x+4=0}

$$\left\{ \begin{array} { l } { 3 x + y = 5 } \\ { 5 x + 4 = 0 } \end{array} \right.$$

Solve for x, y

$$x=-\frac{4}{5}=-0.8$$

$$y = \frac{37}{5} = 7\frac{2}{5} = 7.4$$

Solution Steps

Consider the second equation. Subtract 4 from both sides. Anything subtracted from zero gives its negation.

$$5x=-4$$

Divide both sides by 5.

$$x=-\frac{4}{5}$$

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

$$3\left(-\frac{4}{5}\right)+y=5$$

Multiply 3 and -\frac{4}{5} to get -\frac{12}{5}.

$$-\frac{12}{5}+y=5$$

Add \frac{12}{5} to both sides.

$$y=5+\frac{12}{5}$$

Add 5 and \frac{12}{5} to get \frac{37}{5}.

$$y=\frac{37}{5}$$

The system is now solved.

$$x=-\frac{4}{5} y=\frac{37}{5}$$