[tex]\displaystyle \sqrt[3]{x^2+4x-50}=3\\ x^2+4x-50=27\\x^2+4x-50-27=0\\x^2+11x-7x-77=0\\x(x+11)-7(x+11)=0\\(x+11)(x-7)=0\\x+11=0,x-7=0\\x_1=-11,x_2=7[/tex]