Question

How do you graph the line $y = - 2$?

Answer 1

In the above question, we need to plot the above line on the graph. Since, the given equation is a line where the equation of the straight line is $y = mx + c$ so we can compare with this equation and find out the coordinates of the line on the cartesian plane.

Complete step by step solution:
In the above equation, we have to plot the line on the graph. To find the coordinates of the line what we can do is to select some values of x coordinate and then evaluate those values in the given equation where we get $y = - 2$.

So, we will select a value for x i.e., zero and we substitute the value in $y = mx + c$

Where m is the slope of the equation and c is the constant term y-intercept. So substitute the value in equation we get,
$y = m \times 0 + c$

Since, y should always be equal to -2 so we use m=0 because whatever value we put for $x$will not matter as long m is zero.

Therefore y=-2 so c becomes -2. Here c is the y-intercept, so y-intercept means the line cutting the y - axis.

Therefore, the line is parallel to the x-axis because the value of slope is 0. Since it has no slope the line is in horizontal direction cutting the y-axis at point -2.

Note: An important thing to note is that slope contains the direction in which you go from one point to another. where $m = \dfrac{y}{x} \Rightarrow \dfrac{{rise}}{{run}}$.The numerator tells you many steps to go up and down and denominator tell us how much steps to move left or right.