$\"\"$

The expression is $\"\"$

Subtraction property of equality:

If x + a = b, then x + a - a = b - a, or x = b - a.

$\"\"$ (Subtract 9 from each side)

$\"\"$ (Commutative property: $\"\"$ )

$\"\"$ (Additive inverse property: $\"\"$

$\"\"$ (Subtract: $\"\"$ )

$\"\"$

Check:

Check the solution by substituting $\"\"$ in the original equation.

$\"\"$

$\"\"$ (Subtract: 9 – 3 = 6)

$\"\"$

The value of $\"\"$