Question

Suppose y varies directly as x. If y=-4 when x = 32, find x when y=-0.375.

Answer 1

If y varies directly with x, we have a relation that is:

`y=kx`

where k is a constant.

If we know a point, we can find the constant as:

`k=(y)/(x)=(-4)/(32)=-0.125`

Now we have to calculate x for y=-0.375:

`\begin{gathered} y=kx \\ x=(y)/(k)=(-0.375)/(-0.125)=3 \end{gathered}`

The value for x is 3.