1) 3х^2+5x-1=x^2-4x
3x^2-x^2+5x+4x-1=0
2x^2+9x-1=0
2) 14x+7x^2-2-x=x^2+4x-4x-16
7x^2-x^2+13x-2+16=0
6x^2+13x+14=0
3) 36+12x+x^2=3x-x^2-6+2x
x^2+x^2+12x-5x+36+6=0
2x^2+7x+42=0
4)8x-3x^2=25x^2-10x+1
-3x^2-25x^2+8x+10x-1=0
-28x^2+18x-1=0 умножемь на -1
28x^2-18x+1=0