Question

tim x biet

a)190+x=2009

b)(x-2)*7=642

c)x:7=642

Answer 1

a) 190 + x = 2009

             x = 2009 - 190

             x = 1819

b) (x - 2) x 7 = 642

     x-   2        = 642 : 7

     x -  2         = \(\frac{642}{7}\)

     x               = \(\frac{642}{7}\) +2

     x               = \(\frac{656}{7}\)

c) x : 7 = 642

    x      = 642 x 7 

    x      = 4494

Answer 2

a)190+x=2009

x=2009-190

x=1819. Vậy x=1819

b)(x-2)*7=642

x-2=642/7

x-2=91,7 .......

nói chung đề câu này sai

c)x:7=642

x=642*7

x=4494

Answer 3

a.190+x=2009

=>x=2009-190

=>x=1819

b.(x-2).7=642

=>x-2=642:7

=>x=642/7+2

=>x=656/7

c.x:7=642

=>x=642.7

=>x=4494