x:10+x.3,9=4,8
<=>x.1/10+x.39/10=24/5
<=>x.(1/10+39/10)=24/5
<=>x.4=24/5
<=>x=24/5:4
<=>x=24/5.1/4
<=>x=6/5
vậy x=6/5
x:10 + x.3,9=4,8
=>x.1/10+x.39/10=24/5
=>x.(1/10+39/10)=24/5
=>x. 4 =24/5
=>x =24/5:4
=>x=25/16