Question

 Aflati x :-28x+3x²=95

Answer 1

$3x^{2} -28x-95=0$

Δ = $b^{2} -4ac=(-28) ^{2} -4*3*(-95)=784+1140=1924$

$x_{1} = \frac{-b- \sqrt{delta} }{2a} = \frac{-(-28)- \sqrt{1924} }{6} = \frac{28-2 \sqrt{481} }{6} = \frac{2(14- \sqrt{481)} }{6} = \frac{14- \sqrt{481} }{3} =$$\frac{14-21,93}{3} =- \frac{7,93}{3} =-2,64$

$x_{2} = \frac{-b+\sqrt{delta} }{2a} = \frac{-(-28)+ \sqrt{1924} }{6} = \frac{28+2 \sqrt{481} }{6} = \frac{2(14+ \sqrt{481)} }{6} = \frac{14+ \sqrt{481} }{3} =$$\frac{14+21,93}{3} = \frac{35,33}{3} =11,97$

S={-2,64; 11,97}