Respostas

  • Usuário do Brainly
2014-08-20T21:36:04-03:00
 12x - 10 =x + 11
12x - x = 11 + 10
11x = 21
 x = 21/11
 7x + 5 = 68 - 2x
7x + 2x = 68 - 5
9x =63
x = 63 : 9
x = 7

2014-08-20T21:37:13-03:00
12x - 10 =x + 11 
12x-x = 11+10
11x=21
x=21/11
x=1,90

7x+5=68-2x
7x+2x=68-5
9x=63
x=63/9
x=7