Question: User: $X+X=43$
1. **State the problem:** Solve the equation $X + X = 43$ for $X$.
2. **Combine like terms:** Since $X + X$ is the same as $2X$, rewrite the equation as:
$$2X = 43$$
3. **Isolate the variable:** To solve for $X$, divide both sides of the equation by $2$:
$$\frac{\cancel{2}X}{\cancel{2}} = \frac{43}{2}$$
4. **Simplify:** This gives:
$$X = \frac{43}{2}$$
5. **Final answer:** The solution is:
$$X = 21.5$$