Răspuns:
1 si -5
Explicație pas cu pas:
[tex]\displaystyle x^2+4x-5=0 \\[/tex]
Stim ca:
a=1
b=4
c=-5
Calculam delta
[tex]\Delta=b^2-4ac \\ \Delta=4^2-4\cdot1\cdot(-5) \\ \Delta=36[/tex]
Acum aflam solutiile
[tex]\displaystyle \boxed{X_{1,2}=\frac{-b\pm\sqrt{\Delta} }{2a} }[/tex]
[tex]\displaystyle X1=\frac{-b-\sqrt{\Delta} }{2a} = \frac{-4-6}{2} =\frac{-10}{2}=-5 \\\\ X2=\frac{-b+\sqrt{\Delta} }{2a} = \frac{-4+6}{2}=\frac{2}{2}=1[/tex]
