Question

Suppose y varies directly as x , and y=−319 when x = 29. Based on this information, write a direct variation equation that relates x and y .

Answer 1

`y = - 11x`

Explanation:

If y varies directly as x, then we can write the relation

`y = kx`

where k is the constant of proportionality.

We substitute y=-319 when x=29.

`- 319 = 29k`

This implies that:

`k = ( - 319)/(29)`

`k = - 11`

The variation equation now becomes

`y = - 11x`