$\"\"$

The equation is $\"\"$ .

According to addition property of equality: If a = b then a + c = b + c.

$\"\"$ (Add 9 to each side)

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

$\"\"$ (Add: 6 + 9 = 15) $\"\"$

According to division property of equality:

For any number a, b and c, If a = b then $\"\"$ .

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

$\"\"$ (Cancel common terms)

a = 5 (Divide: $\"\"$ ) $\"\"$

Now, find the value of a = 5.

$\"\"$

$\"\"$ (Multiply: $\"\"$ )

6 = 6 (Subtract: $\"\"$ ) $\"\"$

The value of a = 5.