$\"\"$

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)

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

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

$\"\"$

Check:

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

$\"\"$

$\"\"$ (Add: -7 + 9 = 2)

$\"\"$

The value of $\"\"$