Question

Решите уравнение
Помогите...

Answer 1

$(x^{2}+5x)(x^{2}+5x-5)=6\\\\x^{2}+5x=m\\\\m(m-5)-6=0\\\\m^{2}-5m-6=0\\\\m_{1}=-1\\\\m_{2}=6-teorema.Vieta\\\\x^{2}+5x=6\\\\x^{2}+5x-6=0\\\\x_{1}=-6\\\\x_{2}=1-teorema.Vieta\\\\2)x^{2}+5x=-1\\\\x^{2} +5x+1=0\\\\D=5^{2}-4*1=25-4=21\\\\x_{3}=\frac{-5-\sqrt{21}}{2}\\\\x_{4}=\frac{-5+\sqrt{21}}{2}$