Question

If x varies directly as y, and x = 16 when y = 8, find x when y = 10.

Answer 1

Given that x varies direcrly ay. This can be repsened as below

`\begin{gathered} x\alpha y \\ x=Ky \end{gathered}`

When y=10 , x=16.

Substitute into formular to know their relationship

`\begin{gathered} x=Ky \\ 16=K*8 \\ K=(16)/(8)=2,\text{then} \\ x=2y \end{gathered}`

To Find: find x when y = 10

`\begin{gathered} x=2y \\ y=10 \\ x=2*10 \\ x=20 \end{gathered}`

Hence, when y =10, the value of x is 20