4x+5=5x-4 x=?
问题描述:
4x+5=5x-4 x=?
答
9
答
5x-4x=4+5 x=9
答
移项
5x-4x=5+4
x=9
答
4x+5=5x-4
5-(-4)=5x-4x
9=x
x=9
答
4x+5=5x-4
x=9
答
5x-4x=5+4
x=9