方程1-4/5x=2/5？

Question

如题所述

Answer 1

解：
1-4/5x=2/5
4/5x=1-2/5
4/5x=3/5
x=3/5÷4/5
x=3/5×5/4
x=3/4

Answer 2

1-4/5x=2/5
解：4/5x=1-2/5
4/5x=3/5
x=3/5÷4/5
x=3/5x5/4
x=3/4