Answer:
12 meters
Step-by-step explanation:
Area of square = 144 Sq m
[tex]side \: of \: square = \sqrt{144} \\side \: of \: square = 12 \: m \\ \\ perimeter \: of \: square \: \\ = 4 \times 12 \\ = 48 \: m \\ \\ perimeter \: of \: square \: with \: \\ side \: 9 \: m \\ = 4 \times 9 \\ = 36 \: m \\ \\ diference \: in \: perimeters \\ = 48 - 36 = 12 \: m[/tex]