`x=(2)/(3)` is a solution of `2x+5=8`.

Answer

To determine if \( x = \frac{2}{3} \) is a solution of the equation \( 2x + 5 = 8 \), we will substitute \( x \) with \( \frac{2}{3} \) and check if the equation holds true.

### Step-by-Step Solution:

1. **Substitute \( x \) in the equation**:
\[ 2x + 5 = 8 \]
Replace \( x \) with \( \frac{2}{3} \):
\[ 2\left(\frac{2}{3}\right) + 5 = 8 \]

2. **Multiply \( 2 \) by \( \frac{2}{3} \)**:
\[ \frac{4}{3} + 5 = 8 \]

3. **Convert \( 5 \) to a fraction with a common denominator**:
To add \( \frac{4}{3} \) and \( 5 \), we convert \( 5 \) into a fraction:
\[ 5 = \frac{15}{3} \]
Now we can add:
\[ \frac{4}{3} + \frac{15}{3} = \frac{4 + 15}{3} = \frac{19}{3} \]

4. **Check if \( \frac{19}{3} \) equals \( 8 \)**:
We need to compare \( \frac{19}{3} \) with \( 8 \):
\[ 8 = \frac{24}{3} \]
Now we see if \( \frac{19}{3} = \frac{24}{3} \):
\[ \frac{19}{3} \neq \frac{24}{3} \]

5. **Conclusion**:
Since \( \frac{19}{3} \) does not equal \( 8 \), we conclude that \( x = \frac{2}{3} \) is **not** a solution of the equation \( 2x + 5 = 8 \).