Răspuns :
{[x+(x+1)]*5-2}*4+1=2013
{[x+(x+1)]*5-2}*4=2013-1=2012
[x+(x+1)]*5-2=2012:4=503
[x+(x+1)]*5=503+2=505
x+(x+1)=505:5=101=2x+1=>x=(101-1):2=50
=>x=50
cu rezolvarea completa
{[(x+x+1).5]-2} .4+1=2013 ( 2x+1).5=10x+5 10x+5-2=10x+3 (10x+3).4+1=40x+12+1=40x+13 40x+13=2013 40x=2000 x=50