Question

7х^2-63=0
5х^2+19х-4=0

Answer 1

$===============\7x^2-63=0\ x^2=9\ x=(+-);3\ x=3\ x=-3\===============\ 5x^2+19x-4=0\\ x= frac{-19(+-); sqrt{19^2-4*5*(-4)} }{2*5} \\ x= frac{-19(+-); sqrt{441} }{10} \\x= frac{-19(+-);21}{10} \\x=; -4\\x= frac{1}{5} \\OTVET:;; x_{1} =-4;;|;; x_{2} = frac{1}{5}$