Rip van Winkle fell asleep for a very long time. When he fell asleep, his beard was 888 millimeters long, and each passing week it grew 222 additional millimeters.Graph the length of Rip van Winkle's beard (in millimeters) as a function of time (in weeks).Please help me to understand how to graph this problem.

Let x = time, weeks.
Let y =  length of Rip van Winkle's beard, mm

Initially, his beard was 888 mm long, therefore
When x = 0, y = 888.

For every week, y increases by 222 mm.
Therefore
y = 222x + 888

This is an equation for a straight line with 
slope = 222,
y-intercept = 888

When x = 1, y = 222 + 888 = 1110 mm
To draw the straight line, choose two points:
(0, 888)  from the y-intercept
(1, 1110)

The graph of the straight line is shown below. The two points are shown on the line.