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Rezolvati ecuatia: 4x²+36x=760

Răspuns :

[tex]4x^2+36x=760~~~~~~~|+81 \\ \\ 4x^2+36x+81=841 \\ \\ (2x+9)^2=29^2 \Rightarrow2x+9= \pm 29. \\ \\ 2x+9=-29 \Rightarrow2x=-38 \Rightarrow \boxed{x=-19}. \\ \\ 2x+9=29 \Rightarrow 2x=20 \Rightarrow \boxed{x=10}[/tex]