这两个方程怎么解?①120+(x-120)×40%=1/2x ②120+(x-120)×40%=3/2+3x

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这两个方程怎么解?①120+(x-120)×40%=1/2x ②120+(x-120)×40%=3/2+3x
这两个方程怎么解?
①120+(x-120)×40%=1/2x ②120+(x-120)×40%=3/2+3x

这两个方程怎么解?①120+(x-120)×40%=1/2x ②120+(x-120)×40%=3/2+3x
①120+(x-120)×40%=1/2x
120+0.4x-48=0.5x
0.5x-0.4x=120-48
0.1x=72
x=720
②120+(x-120)×40%=3/2+3x
120+0.4x-48=1.5+3x
3x-0.4x=120-48-1.5
2.6x=70.5
x=705/26

(1)120+(x-120)×40%=1/2x
120+(x-120)×0.4=0.5x
0.4X - 48 - 0.5x = -120
-0.1X = -120 + 48
X = 720
(2) 120+(x-120)×40%=3/2+3x
120+(x-120)×0.4=1.5+3x
0.4X - 48 - 3X = 1.5 - 120
-2.6X =-118.5 + 48
X = 2.7115