1: \(\Rightarrow x^2-10x+18-x^2=12\)
=>-10x=-6
hay x=3/5
2: \(\Leftrightarrow4x^2+3x-4x^2+8x=10\)
=>11x=10
hay x=10/11
3: \(\Leftrightarrow5x^2-15x+5+x-5x^2=x-2\)
=>-14x+5=x-2
=>-15x=-7
hay x=7/15
4: \(\Leftrightarrow12x^2-12x^2+20x=10x-17\)
=>10x=-17
hay x=-1,7



