Răspuns: 2
Explicație pas cu pas:
[tex]\displaystyle \frac{1}{2} \ + \ \frac{x-1}{5} \ = \ \frac{7}{10} \ \ / \cdot \ 10 \\\\5 \ + \ 2\ \cdot \ (x \ - \ 1) \ = \ 7 \\\\5 \ + \ 2x\ - \ 2 \ = 7\\\\5 \ + \ 2x \ = \ 7 \ + \ 2 \\\\5 \ + \ 2x\ = \ 9 \\\\2x \ = \ 9 \ - \ 5 \\\\2x \ = \ 4 \\\\x \ = \ 4 \ : \ 2 \\\\x = \boxed { 2 }[/tex]
