( 15-x ) + 2x = 2016-4
( 15-x ) + 2x = 2012
15-x + 2x = 2012
Vì - x + 2x = x nên có :
15 + x = 2012
x = 2012 - 15
x = 1997
(15-x)+2x=2016-2
(15-x)+2x=2012
15x1-Xx1=2012
1(15-x)=2012
15-x=2012:1
15-x=2012=>x=15-2012=-1997
(15-x)+2x=2016-4
15-x+2x=2012
15+x=2012
x=2012-15
x=1997
(15-x)+2x=2016-4
15-x +2x =2012
15+x=2012
x= 1997