Question

The slope of any line which is parallel to $x$-axis is ………… .
A) 0
B) 1
C) -1
D) 2

Answer 1

Here we need to find the slope of the line which is parallel to the $x$-axis. For that, we will first find the equation of a line which is parallel to the $x$-axis. Then we will compare the equation of the line obtained with the standard equation of the line. From there, we will get the value of the slope of the line which is parallel to x-axis. Angle made by the line with the $x$-axis is zero.

Complete step by step solution:
We know the equation of a line which is parallel to x-axis is given by
$y = 0$ ……. $\left( 1 \right)$
We know the standard equation of a line is given by
$y = mx + c$ ……… $\left( 2 \right)$
Here, $m$ is the slope of the line and $c$ is the constant.
On comparing equation $\left( 1 \right)$ and equation $\left( 2 \right)$, we get
$\Rightarrow m = 0$
Thus, the slope of the line parallel to $x$-axis is equal to 0.

Hence, the correct option is option A.

Note:
We have obtained the slope of the line which is parallel to $x$-axis. The slope of a line is defined as a ratio of change in $y$ coordinate of any two points of a line to the $x$ coordinate of the same two points of a line. If the value of the slope is zero, then the line is parallel to $x$-axis. If the value of the slope is 1, then the line is perpendicular to the $x$-axis. If the value of the slope is greater than zero, then the line goes up from left to right and if the value of the slope is less than zero, then the line goes down from left to right.