Answer
$\frac{9}{49}$
Work Step by Step
To square a number, we multiply the number by itself. Therefore: $$(-\frac{3}{7})^2=(-\frac{3}{7})\times(-\frac{3}{7}).$$
To multiply two fractions, we multiply the numerators and the denominators: $$(-\frac{3}{7})\times(-\frac{3}{7})=\frac{(-3)\times(-3)}{7\times7}=\frac{9}{49}$$
