Respostas

2014-05-16T17:20:21-03:00
2x-10/20 + 4-8x/20 = 15-5x/20
eliminando o 20 fica
2x-10+4-8x=15-5x
-6x-6=15-5x
-6x+5x=15+6
-x=21 .(-1)
x=-21