1. **State the problem:** Determine which expressions always yield an even value when $x$ is an even number.
2. **List the expressions:**
- Expression A: $\frac{x}{2}$
- Expression B: $9x + 2$
- Expression C: $15 + x$
- Expression D: $\frac{4x}{2}$
3. **Recall important rules:**
- An even number is any integer divisible by 2.
- When $x$ is even, $x = 2k$ for some integer $k$.
- We will substitute $x=2k$ into each expression and simplify.
4. **Evaluate Expression A: $\frac{x}{2}$**
$$\frac{x}{2} = \frac{2k}{2} = \cancel{\frac{2}{2}}k = k$$
Since $k$ can be any integer, $k$ can be even or odd, so $\frac{x}{2}$ is not always even.
5. **Evaluate Expression B: $9x + 2$**
Substitute $x=2k$:
$$9(2k) + 2 = 18k + 2 = 2(9k + 1)$$
Since $9k + 1$ is an integer, $9x + 2$ is always even.
6. **Evaluate Expression C: $15 + x$**
Substitute $x=2k$:
$$15 + 2k$$
Since 15 is odd and $2k$ is even, odd + even = odd, so $15 + x$ is always odd, not even.
7. **Evaluate Expression D: $\frac{4x}{2}$**
Substitute $x=2k$:
$$\frac{4(2k)}{2} = \frac{8k}{2} = \cancel{\frac{8}{2}}k = 4k$$
Since $4k$ is divisible by 2, it is always even.
**Final answer:** Expressions that always have an even value when $x$ is even are:
- $9x + 2$
- $\frac{4x}{2}$
Even Value 223D3F
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