7x+5.3=7.4解7x=2.1x=0.3检验，把x=0.3带入原方程可得7×0.3+5.3=7.4所以x=0.3
7x=2.1x=0.37*0.3+5.3=2.1+5.3=7.4满意请采纳哦
7x=7.4－5.3 7x=2.1 x=0.3
7x=2.1 x=3
N0
