2x=9/8-3/42x=3/8x=3/166x=1/10+7/86x=39/40x=13/804/9x-3/9x=11/9x=1x=1/91/6x=4/3-11/121/6x=16/12-11/121/6x=5/12x=2/5[8/4-3/4]x=4/55x/4=4/55x=16/5x=16/25此题可能有误。应为4x/7+x=22/4911x=22/7x=2/7.如按所写,为二次方程,恐怕不是同一层次