Question

Tìm x

9x - 2x = 30 - 20 : 10

Answer 1

9x - 2x = 30 - 20 : 10

7x        = 30 - 2

7x        = 28

x          = 28 : 7

x         = 4

Answer 2

9x - 2x = 30 -20 : 10

<=> 9x - 2x = 28

<=> 7x = 28

=> x = 28 : 7

Vậy x=4 :D

Answer 3

\(9x-2x=30-20:10\)

\(x.\left(9-2\right)=28\)

\(x.7=28\)

\(x=28:4\)

\(x=7\)