Question

The variables x and y vary directly. Write an equation that relates the variable. Then find x when y=16.

Answer 1

7) We know that x = 5 and y = 2

We can write an equation that relates this values as a proportion.

Let's say there is a number r such as:

x*r=y

That's a equation that relates x and y. Let's solve for the values given.

`5\cdot r=2`

Now solve for r:

`r=(2)/(5)`

The relation we found is:

`x\cdot(2)/(5)=y`

Now to find the value of x when y = -6, we replace it in the equation:

`\begin{gathered} x\cdot(2)/(5)=-6 \\ x=-6\cdot(5)/(2)=-15 \end{gathered}`

Then with this relation, x = -15 when y = -6