Construct a linear model from a description

Let \(H\) represent height in cm, and let \(m\) represent time elapsed in months. One unit of \(m\) represents 1 month

At the start of the observations, a child has a height of 57 cm. Its height then increases by 2 cm per month

Fractional input values are permitted within the stated interval

The linear model is claimed for \(0 \le m \le 12\)