Subtract :
`-1/2 ab " from " -2/3 ab `

Answer

To solve the problem of subtracting \(-\frac{1}{2}ab\) from \(-\frac{2}{3}ab\), we can follow these steps:

### Step 1: Write the expression for subtraction
We need to subtract \(-\frac{1}{2}ab\) from \(-\frac{2}{3}ab\). This can be written as:
\[ -\frac{2}{3}ab - \left(-\frac{1}{2}ab\right) \]

### Step 2: Simplify the expression
When we subtract a negative, it becomes addition:
\[ -\frac{2}{3}ab + \frac{1}{2}ab \]

### Step 3: Find a common denominator
To add the fractions, we need a common denominator. The denominators are 3 and 2. The least common multiple (LCM) of 3 and 2 is 6.

### Step 4: Convert each fraction to have the common denominator
Convert \(-\frac{2}{3}ab\) and \(\frac{1}{2}ab\) to have a denominator of 6:
\[ -\frac{2}{3}ab = -\frac{2 \times 2}{3 \times 2}ab = -\frac{4}{6}ab \]
\[ \frac{1}{2}ab = \frac{1 \times 3}{2 \times 3}ab = \frac{3}{6}ab \]

### Step 5: Combine the fractions
Now we can add the two fractions:
\[ -\frac{4}{6}ab + \frac{3}{6}ab = \frac{-4 + 3}{6}ab = \frac{-1}{6}ab \]

### Final Answer
Thus, the result of subtracting \(-\frac{1}{2}ab\) from \(-\frac{2}{3}ab\) is:
\[ -\frac{1}{6}ab \]

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