$\"\"$

The equation is $\"\"$

$\"\"$ (Multiply each side by 3)

$\"\"$ (Cancel common terms) \ \

$\"\"$ (Divide each side by b)

$\"\"$ (Cancel common terms)

$\"\"$ (Subtract $\"\"$ from each side)

$\"\"$ (Additive inverse proeprty: $\"\"$ )

$\"\"$ (Simplify)

$\"\"$

Verify:

To check the solution, substitute $\"\"$ in original equation.

$\"\"$

$\"\"$ (Cancel common terms)

$\"\"$ (Additive inverse proeprty: $\"\"$ )

$\"\"$ (Cancel common terms)

Compare the values, the equation is true.

$\"\"$

The value of $\"\"$ .