The slope of *x* -axis is zero and the slope of *y* -axis is not defined. ** HOW AND WHY ?? **

The said line in our study material is:

slope of x-axis is zero and the slope of y-axis is not defined.

Here, we are talking about the slope of both the axis with respect to horizontal.

In case of x-axis, θ = 0° and in case of y -axis, θ = 90°.

So, slope of x -axis = tan θ = tan 0° = 0

Similarly, slope of y -axis = tan θ = tan 90° and we know that value of tan 90° is undefined.

So, this is the only reason why slope of y-axis is undefined.

Hope you get it!!

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