[tex]\displaystyle\bf 4x^2+3=-7x\\4x^2+7x+3=0 \\\\D=49-48=1 \\x_1=\frac{-7+1}{8} =-\frac{3}{4} \\x_2=\frac{-7-1}{8} =-1\\\\Answer: \boxed{ x_1=-\frac{3}{4} \quad ; \quad x_2=-1}[/tex]