2x^2-x=-3x^2-3x+5x^2+3
4x^2+2x-3=0
4(x^2+1/2x)-3=0
4(x^2+1/2x+1/16-1/16)-3=0
4(x+1/4)^2-1/4-3=0
(x+1/4)^2=13/16
x1=-1/4+√13/4
x2=-1/4-√13/4望采纳望采纳手机点击评价,选择左边问题已解决