Solve {l}{3x-1=x+5}{7a+8=3a-1}

$$\left. \begin{array} { l } { 3 x - 1 = x + 5 } \\ { 7 a + 8 = 3 a - 1 } \end{array} \right.$$

Solve for x, a

$$x=3$$

$$a = -\frac{9}{4} = -2\frac{1}{4} = -2.25$$

Solution Steps

Consider the first equation. Subtract x from both sides.

$$3x-1-x=5$$

Combine 3x and -x to get 2x.

$$2x-1=5$$

Add 1 to both sides.

$$2x=5+1$$

Add 5 and 1 to get 6.

$$2x=6$$

Divide both sides by 2.

$$x=\frac{6}{2}$$

Divide 6 by 2 to get 3.

$$x=3$$

Consider the second equation. Subtract 3a from both sides.

$$7a+8-3a=-1$$

Combine 7a and -3a to get 4a.

$$4a+8=-1$$

Subtract 8 from both sides.

$$4a=-1-8$$

Subtract 8 from -1 to get -9.

$$4a=-9$$

Divide both sides by 4.

$$a=-\frac{9}{4}$$

The system is now solved.

$$x=3 a=-\frac{9}{4}$$