2. Given:
[tex]y=7z[/tex]
To classify the equation as direct, inverse or joint variation then state the constant of variation:
It is of the form,
[tex]y=kz,\text{ whe}re\text{ }k\text{ is the constant}[/tex]
If y increases then z increases and if y decreases then z decreases.
Therefore, it is direct variation.
We know that the ratio between two variables in a direct variation is a constant of variation.
Thus, the constant of variation is k = 7.
