Question

X²-{3x+[x(x+1)+4(x²-1)-4x²]}=0

Answer 1

x$x^{2} -(3x+(x^{2} +x+4(x^{2} -1)-4x^{2} )=0 \\ x^{2} -(3x+(x^{2} +x+4x^{2} -4-4x^{2})=0 \\ x^{2} -(3x+x^{2} +x-4)=0\\ x^{2} -(4x+x^{2} -4)=0\\ x^{2} -4x-x^{2} +4=0\\ -4x+4=0\\ -4x=-4\\ x=1$