Question

How do you graph a linear equation?

For example, -18x+9y=72

Answer 1

Basically with the example you have you need to have the x and y variables on different sides.
Equation:
-18x+9y=72 (now you want to add 18x on both sides)
+18x +18x
9y=72+18x (next you divide 9 to both sides to get x and y alone)
9
y=8+2x (now that you have the x and y alone this is the final equation)

On the graph you want to put a dot on 8 since it's the y-intercept or the starting point of the equation. After that you want to add 2 every time you go by 1 on the x-axis. I have a picture of a graph...

I hope this help you out :D

Answer 2

The graph of given equation is shown below.

Explanation:

We need to draw the graph of linear equation.

Let as consider a linear equation.

`-18x+9y=72`

First we need to find any two points on the line. So, will find x and y-intercept of the line.

Substitute x=0 in the given equation to find the y-intercept.

`-18(0)+9y=72`

`9y=72`

Divide both sides by 9.

`y=8`

⇒ y-intercept of the line is 8.

Substitute y=0 in the given equation to find the x-intercept.

`-18x+9(0)=72`

`-18=72`

Divide both sides by -18.

`y=-4`

⇒ x-intercept of the line is -4.

Now, plot these two points (0,8) and (-4,0) on a coordinate plane and connect them by a straight line.

Therefore, the graph of given equation is shown below.