x-20%x+9=5/4x

问题描述:

x-20%x+9=5/4x

解, x-1/5x+9=5/4x(两边通分乘以20)
20x-4x+9=25x
180=25x-20x+4x
9x=180
x=20

x-20%x+9=5/4x
X-0.2X+9=1.25X
9=0.45X
20=X
X=20

解,x-1/5x+9=5/4x(两边通分乘以20)
20x-4x+9=25x
180=25x-20x+4x
9x=180
x=20
或x-20%x+9=5/4x
X-0.2X+9=1.25X
9=0.45X
20=X
X=20