Tacó:x×(2013-1)=2013×(2011+1)
X×2012=2013×2012
X×2012=4050156
X=4050156÷2012
X=2013
x*(2013-1)=2013*(2011+1)
x*2012=2013*2012
x=2013
x * 2013 - x = 2013 * 2011 + 2013
=> x * ( 2013 -1 ) = 2013 * (2011 +1 )
=> x * 2012 = 2013 * 2012
=> x = 2012
Vậy x = 2012 là giá trị cần tìm