I don't know what you are talking about please re word the question its really hard to understand what your asking.
H=height
y=number of years.
we have the next expresion:
h(y)=my+b
m=the slope of the line, in this case, the slope is equal to "18"; (18 cm/ year).
b=the initial heigth, in this case, the initial heigth is equal to "5" (5 cm).
Therefore, our expression will be:
h(y)=18y +5
answer: h(y)=18y+5
