$\"\"$ $\"\"$

The inequlaity is $\"\"$ .

Apply addition property of inequality: Add 3.5 to each side.

$\"\"$

$\"\"$ (Apply additive inverse property: $\"\"$ )

$\"\"$ (Apply additive identity property: $\"\"$ )

$\"\"$ (Divide: $\"\"$ )

$\"\"$ (Add: $\"\"$ ) $\"\"$

Check:

To substitute a number less than 3.9 in $\"\"$ .

$\"\"$ (Substitute a = 3)

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

The inequality is true $\"\"$

The inequality solution set is $\"\"$ .