\(2+x-13=7-9\)
\(\Rightarrow2+x-13=-2\)
\(\Rightarrow x=-2-2+13\)
\(\Rightarrow x=9\)
Vậy.........
2+x-13=7-9
2+x=-2+13
2+x=11
x=11-2
x=9
.......................................................................................................................
<=>2+x-13=-2
<=>2+x=11
<=>x=9
Vậy x=9