1. Let's clarify the problem: We want to determine if the x-component of vector $\mathbf{H}$ is negative because it is "at the back of x". 2. In vector components, the sign of the x-component depends on the direction along the x-axis. If the vector points in the negative x-direction, its x-component is negative. 3. The phrase "at the back of x" usually means the vector points opposite to the positive x-axis direction. 4. Therefore, if vector $\mathbf{H}$ points to the left (assuming right is positive x), its x-component is negative. 5. In summary, yes, the x-component of vector $\mathbf{H}$ is negative if it points behind or opposite the positive x-axis direction. Final answer: The x-component of vector $\mathbf{H}$ is negative if it points in the negative x-direction ("at the back of x").