Question

Решите уравнения:
х²=-9х-8
х²-20х=-5х-13-х²

Answer 1

$x^{2} +9x+8=0 \ D=81-32=49 \ sqrt{D}=7 \ x_{1}= frac{-7+7}{2}=0 \ x_{2}= frac{-7-7}{2}=-7$

$x^{2} -20x+5x+13+ x^{2} =0 \ 2 x^{2} -15x+13=0 \ D=121 \ sqrt[n]{D}=11 \ x_{1}= frac{15+11}{4}=6.5 \ x_{2}= frac{15-11}{4}=1$