5(x в квадрате)-45=
81-9(p вкадрате)=
5X^2=45
x^2=9
x1=3
x2=-3
---------
-9x^2=-81
5х^2-45-81+9X^2=0
(5x^2+9x^2)-(45+81)=0
14x^2-126=0
14x^2=126
x^2=126/14