Question

3) The value of y varies directly with x, and y =-3 when x =1. Find y when x =-6.

Answer 1

If the value of y varies directly with x, means that there is a constant of proportionality

`y=kx`

use that y=-3 when x=1

`\begin{gathered} -3=k\cdot(1) \\ -3=k \end{gathered}`

use k to find y when x=-6

`\begin{gathered} y=-3(-6) \\ y=18 \end{gathered}`