4х^4-37х^2+9=0 помогите :)

[latex]4 x^4-37 x^{2} +9=0[/latex] [latex] x^{2} =t[/latex] [latex] 4t^{2} -37t+9=0[/latex] a=4  b=-37   c=9 D=b²-4ac=37²-4*4*9=1225=35² [latex]t1= \frac{-b+ \sqrt{D} }{2a} = \frac{37+35}{8} = \frac{72}{8} =9[/latex] [latex]t2= \frac{-b- \sqrt{D} }{2a} = \frac{37-35}{8}= \frac{2}{8} = \frac{1}{4} [/latex] x²=9                   x²=1/4 x=-3                  x=1/2 x=3                    x=-1/2