Question

How do you graph $y=-9x$?

Answer 1

Hint: First, we have to make the given linear equation in Slope-intercept form and then calculate the value of $y$ for any two arbitrary values of $x$. Next make a table of these values of $x$ and $y$. Next plot the obtained points on the graph paper and draw a line passing through these points.
Slope Intercept form of a line:
The equation of a line with slope $m$ and making an intercept $c$ on $y$-axis is $y=mx+c$.

Complete step by step solution:
Given linear equation in two variables: $y=-9x$
First, we have to make the given linear equation in Slope-intercept form.
Here, the equation is already in Slope-intercept form.
Now, we have to calculate the value of $y$ for any two arbitrary values of $x$. Thus, finding the value of $y$ when $x=0$ and $x=1$.
When $x=0$, $y=-9\times 0=0$
When $x=1$, $y=-9\times 1=-9$
Now we have to make a table of these values of $x$ and $y$.

$x$	$0$	$1$
$y$	$0$	$-9$

Now we have to plot the points $A\left(0,0\right)$ and $B\left(1,-9\right)$ on the graph paper and draw a line passing through $A$ and $B$.

Note: Method to draw the graph of linear equation in two variables:
Step I: Write a given linear equation and express y in terms of x.
Step II: Put different values of x and find the corresponding value of y.
Step III: Form a table by writing the values of y below the corresponding values of x.
Step IV: Plot these points on graph paper.
Step V: Join these points. Thus, we get a straight line and produce it on both sides.