Respuestas

2013-11-07T05:34:20+01:00
7(x-3)-5(x+2)+11(x+1) =19
7X - 21 - 5X - 10 + 11X + 11 =19 
7X - 5X + 11X = 19+21+10-11
13X = 39
X=  \frac{39}{13}
X=3

R// X=3
2013-11-07T10:17:16+01:00
7(X-3)-5(X+2)+11(X+1)=19
7x - 21 - 5x - 10 + 11x +11 = 19 
7x - 5x + 11x = 19 + 21 + 10 - 11
13x = 39
x = 39/13
x = 3