Question

tìm x 

x*2+x*3=4

x*9-1,5=30

Answer 1

`x xx2+x xx3=4`

`x xx(2+3)=4`

`x xx5=4`

`x=4:5=4/5`

_______________________

`x xx9-1,5=30`

`x xx9=30+1,5`

`x xx 9=31,5`

`x=31,5:9`

`x=3,5`

Answer 2

\(x\times2+x\times3=4\)

\(x\times\left(2+3\right)=4\)

\(x\times5=4\)

\(x=4:5\)

\(x=\dfrac{4}{5}\)

 

\(x\times9-1,5=30\)

\(x\times9=30+1,5\)

\(x\times9=31,5\)

\(x=31,5:9\)

\(x=3,5\)

Answer 3

a,X x 2 + X x 3=4
   X x(2+3)       =4
   X x 5             =4
   X                   4/5
b, 9xX-1,5=30
    9xX      =30+1,5=31,5
        X      = 31,5:9
        X      =3,5