Basic Algebra

If $$p^2 + q^2 - 29 = 2pq - 20 = 52 - 2pq$$, then the difference between the maximum and minimum possible values of $$(...

The number of integer solutions of the equation $$ 2|x|(x^2 + 1) = 5x^2 $$ is: ...

If $$\sqrt{5x + 9} + \sqrt{5x - 9} = 3(2 + \sqrt{2}),$$ then $$\sqrt{10x + 9} \text{ is equal to }$$...