$\"\"$

The find out length:

Area of the rectangle is $\"\"$ where l is the length and w is the width.

$\"\"$ (Substitute A = 30.6 and w = 5.1)

$\"\"$ (Divide each side by 5.1)

$\"\"$ (Cancel common terms)

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

The length of the rectangle $\"\"$ m.