Question

X^2+26x+105=0 Через дискриминант

Answer 1

$\displaystyle x^2+26x+105=0\;\;\;\;\; \boxed{a=1\;\;\;\;b=26\;\;\;\;c=105}\\\\D=26^2-4*1*105=676-420=\sqrt{256} =16^2\\\\x_1=\frac{-26-\sqrt{256} }{2*1} =\frac{-26-16}{2} =\frac{-42}{2} =-21\\\\x_2=\frac{-26+\sqrt{256} }{2*1} =\frac{-26+16}{2} =\frac{-10}{2} =-5\\\\\\ \boxed{x_1=-21\;\;\;\;\;x_2=-5}$