a)
[tex]x + x + \frac{1}{2} = 3 \\ 2x + \frac{1}{2} = 3 \\ 2x = 3 - \frac{1}{2} \\ 2x = \frac{6 - 1}{2} \\ 2x = \frac{5}{2} \\ x = \frac{5}{2} \div 2 \\ x = \frac{5 \times 1}{2 \times 2} \\ x = \frac{5}{4} [/tex]
b)
[tex]x + x + \frac{1}{3} + x + \frac{2}{3} = 12 \\ 3x + \frac{3}{3} = 12 \\ 3x + 1 = 12 \\ 3x = 12 - 1 \\ 3x = 11 \\ x = \frac{11}{3} [/tex]
c)
[tex]x + x + \frac{1}{2} = \frac{1}{2} \\ 2x = \frac{1}{2} - \frac{1}{2} \\ 2x = 0 \\ x = 0 \div 2 \\ x = 0[/tex]
d)
[tex]3x = \frac{x}{2} \\ 3x \times 2 = x \\ 6x = x \\ 6x - x = 0 \\ 5x = 0 \\ x = 5 \div 0 \\ x = 0[/tex]
e)
[tex]x + 2 = x - 2 \\ 2 = - 2 \\ [/tex]
de unde rezulta ca relatia e falsa pt orice val a lui x
