An alternative method for plotting the straight line, as mentioned, is to do it straight from the equation. In the equation y = mx + c, m is the gradient, and c is the y-intercept. Thus, here the gradient must be 2 and the y-intercept must be -3.
So, we know that the line passes through (0, -3), and we know that because the gradient is 2, each time the x value increases by 1, the y value increases by 2. This tells us that there must be another point 1 across and 2 up from (0, -3), meaning we can plot these two points, draw a straight line through them, and voila. This method is wordy to explain, but honestly once you practise it, you can get really quick at it
Sometimes the equations of straight lines aren’t given to you in the y = mx + c form, and you have to rearrange them in order to make this method doable.
Example: Plot the straight-line graph with equation 3y + 9x = 12.