[latex]1) \frac{1}{5} x^{2}-5=0| 2) 9 y^{2}- 6,35 = 0|3) 1,44- x^{2} =3 x^{2}|4) \frac{5}{7} x^{2} =-3,5+ x^{2}| [/latex]

[latex] \frac{1}{5} x^2-5=0[/latex] [latex] \frac{1}{5}x^2=5 [/latex] [latex]x^2=25[/latex] [latex]|x=5[/latex] [latex]|x=-5[/latex] [latex]9y^2-6.35=0[/latex] [latex]9y^2=6.35[/latex] [latex]y^2= \frac{6.35}{9} [/latex] [latex]|y= \sqrt{ \frac{635}{900} } [/latex] [latex]|y=- \sqrt{ \frac{635}{900} } [/latex] [latex]1.44-x^2=3x^2[/latex] [latex]x^2+3x^2=1.44[/latex] [latex]4x^2=1.44[/latex] [latex]x^2= \frac{1.44}{4} [/latex] [latex]|x= \frac{1.2}{2} [/latex] [latex]|x=- \frac{1.2}{2} [/latex] [latex]|x=0.6[/latex] [latex]|x=-0.6[/latex] [latex] \frac{5}{7} x^2=-3.5+x^2[/latex] [latex] \frac{5}{7} x^2-x^2=-3.5[/latex] [latex]- \frac{2}{7}x^2=-3.5[/latex] [latex]x^2=12.25[/latex] [latex]|x=-3.5[/latex] [latex]|x=3.5[/latex]