解方程提高训练 X X= 2X + = 70%X + 20%X = 3.6 X=20 25% + 10X = X - 15%X = 68 XX121 5X3 X12 6X5 =13.4 3X= X= XX= 4X6=2 X= X = X = X = 4x3 9 = 29 x + x = 4 X21=4 6X5 =13.4 X-X= 4638 0.365- x = 5X= X= X= (x- 4.5) = 7 X=12 X= X= x- 25%x = 10X= X-0.25= =30% x- 0.8x = 16+6 4+0.7X=102 X+X=42 X+X=105 20 x 8.5= 1.5 X-X=400 X-0.125X=8 = x- x -4= 21 X+X=18 X( + )= x0.375x= X25%X=90 x+=4 XX12 5 X2.458 XX=