algebra

Two positive numbers and have the property that their sum is equal to their product. If their difference is 7, what is $\frac{1}{\frac{1}{p^2}+\frac{1}{q^2}}$? Your answer will be of the form $\frac{a+b\sqrt{c}}{d}$, where a and b don't both share a common factor with d and c has no square as a factor. Find a+b+c+d.