We can put this in y-intercept form,
y = mx + b, where m is the slope, and b is the y-intercept.
If she is currently 104 cm tall, she starts out at that height.
x can represent the number of years.
2.2 represents the number of cm per year, the slope.
The function that best fits this equation is:
y = 2.2x + 104
Hope this helps! :)