p2−4q2=0p^{2}-4 q^{2}=0p2−4q2=0
q2−5p2=0q^{2}-5 p^{2}=0q2−5p2=0
q2−4p2=0q^{2}-4 p^{2}=0q2−4p2=0
p2−5q2=0p^{2}-5 q^{2}=0p2−5q2=0
