Question

√3x^2+25x+51=7+2x (под kорнeм многочлeн до =)

Answer 1

$sqrt{3x^2+25x+51}=7+2x$

$(sqrt{3x^2+25x+51})^2=(7+2x)^2$

$3x^2+25x+51=4x^2+28x+49$

$4x^2+28x+49-3x^2-25x-51=0$

$x^2+3x-2=0$

D=9-4*1*(-2)=9+8=17

$x_1=frac{-3+sqrt{17}}{2}$

$x_2=frac{3-sqrt{17}}{2}$