How do you graph the equation #y=-2x#?
Substitute values into
Draw a line connecting the points extending it to the edge of the graph paper. You may use a minimum of two values but I would suggest 3. If all three do not sit on the line then your maths is wrong somewhere.
What are called critical points for a straight line graph are where the line crosses the axes. So we can calculate the critical points and draw your line as mentioned above.
There is one problem with this equation. It only has 1 critical point. It crosses the axes at the point where they meet (the origin). So you still have to use method 1 to calculate at least one other point.