Question

How do you graph `2x-2y=2` by plotting points?

Answer 1

Set one variable to 0 to find the value of the other variable, graph the points then draw the line.

Explanation:

We're working with a line - we know this because both the x and y terms are of power 1 (so they aren't squared or square-rooted or anything like that). With a line, it takes 2 points and we can then draw a line between them and have that line extend both ways into infinity.

The equation lends itself to setting one variable to 0 and seeing what the resulting other variable will be, like this:

`2x-2y=2`

set x to 0:

`-2y=2`

`y=-1`

so one point is `(0,-1)`

now set y to 0:

`2x=2`

`x=1`

the other point is `(1,0)`

and we can graph those two points and draw the line:

graph{2x-2y=2 [-10, 10, -5, 5]}