Solve {l}{7a+4b=1}{4+2b=7}

$$\left. \begin{array} { l } { 7 a + 4 b = 1 } \\ { 4 + 2 b = 7 } \end{array} \right.$$

Solve for a, b

$$a=-\frac{5}{7}\approx -0.714285714$$

$$b = \frac{3}{2} = 1\frac{1}{2} = 1.5$$

Solution Steps

Consider the second equation. Subtract 4 from both sides.

$$2b=7-4$$

Subtract 4 from 7 to get 3.

$$2b=3$$

Divide both sides by 2.

$$b=\frac{3}{2}$$

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

$$7a+4\times \frac{3}{2}=1$$

Multiply 4 and \frac{3}{2} to get 6.

$$7a+6=1$$

Subtract 6 from both sides.

$$7a=1-6$$

Subtract 6 from 1 to get -5.

$$7a=-5$$

Divide both sides by 7.

$$a=-\frac{5}{7}$$

The system is now solved.

$$a=-\frac{5}{7} b=\frac{3}{2}$$