−2x is the gradient (or steepness) of the line. The gradient tells us that for 1 square to the right, how many squares we go up or down. With a negative number, we go downwards, and with a positive one we go up. this means that for every 1 square we go to the right, we go down −2.
−4 is the y-intercept, which shows us at which point on the y-axis (vertical axis) the line crosses. Therefore, the line will cross the y-axis at −4.
to draw the line, plot a point on he coordinate (0,−4), then go 1 box across and 2 down, and plot a second point. Continue to do this until you no longer can. Then work the opposite direction, going 1 to the left and 2 up