1. The problem is to simplify the expression $\frac{7}{10} - \left(-\frac{1}{2}\right)$.\n\n2. Recall that subtracting a negative number is the same as adding its positive counterpart, so $a - (-b) = a + b$.\n\n3. Apply this rule: $\frac{7}{10} - \left(-\frac{1}{2}\right) = \frac{7}{10} + \frac{1}{2}$.\n\n4. To add fractions, find a common denominator. The denominators are 10 and 2. The least common denominator (LCD) is 10.\n\n5. Convert $\frac{1}{2}$ to a fraction with denominator 10: $\frac{1}{2} = \frac{5}{10}$.\n\n6. Now add: $\frac{7}{10} + \frac{5}{10} = \frac{7+5}{10} = \frac{12}{10}$.\n\n7. Simplify $\frac{12}{10}$ by dividing numerator and denominator by 2: $\frac{12}{10} = \frac{6}{5}$.\n\n8. The simplified result is $\frac{6}{5}$ or $1 \frac{1}{5}$.