Question

Irect Variation

Answer 1

For this case we have to by definition, if "y" varies directly with "x" then it is true that:

$y = kx$

Where:

k: Is the constant of proportionality

We find the constant "k" according to the given data:

$14 = k (-4)\\k = - \frac {14} {4} = -\frac {7} {2}$

Thus, the constant of proportionality is $- \frac {7} {2}.$

Now, we find the value of "y" when $x = -6:$

$y = - \frac {7} {2} (- 6)\\y = \frac {42} {2}\\y = 21$

Thus, when$x = -6$, the value of y is 21.

ANswer:

$y = 21$