tìm x
1, \(0,4\cdot x-\frac{1}{5}x=\frac{3}{4}\)
2, \(x\div1\frac{2}{7}=-3,5\)\
3, \(\left(\frac{2x}{5}-2\right)\div\left(-5\right)=\frac{3}{7}\)
4, x+ 20% x = -4,8
5, \(x-15\%x=-2\frac{11}{20}\)
6, \(\left(x\cdot25\%-\frac{2}{3}\right)\div2\frac{1}{3}=1\frac{5}{8}\)
1. 0,4x - 1/5x = 3/4
=> 1/5x = 3/4
=> x = 3/4 : 1/5
=> x = 15/4
2.
x : 1 2/7 = -3,5
=> x = -3,5 . 9/7
=> x = -9/2