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.
