You have to multiply the fractions
[tex](-\frac{2}{7})\cdot(-\frac{3}{7})[/tex]First note that both values are negative. As a rule, when two negative values are mutiplied, the result will be positive, always.
Next, you have to multiply the numerators together and the denominators together as follows:
[tex]\frac{2}{7}\cdot\frac{3}{7}=\frac{2\cdot3}{7\cdot7}=\frac{6}{49}[/tex]