The equation of X-axis is

Options

A. `x=0,y=0`
B. `y=0,z=0`
C. `x=0,z=0`
D. `y=0`

Answer

To find the equation of the X-axis, we can follow these steps:

### Step 1: Understand the Definition of the X-axis
The X-axis is the horizontal line in a 3D coordinate system where the Y and Z coordinates are always zero.

### Step 2: Write the General Form of a Point on the X-axis
A point on the X-axis can be represented as (x, 0, 0), where:
- x can take any real number value,
- The Y-coordinate is 0,
- The Z-coordinate is 0.

### Step 3: Formulate the Equation
From the understanding that any point on the X-axis has Y and Z coordinates equal to zero, we can express the equation of the X-axis as:
- Y = 0
- Z = 0

### Step 4: Conclusion
Thus, the equation of the X-axis in a 3D coordinate system can be summarized as:
- The set of all points (x, 0, 0) where x ∈ ℝ (any real number).

### Final Answer
The equation of the X-axis is:
- Y = 0 and Z = 0.

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