Question

The variables y and x have a proportional relationship, and y = 5 when x = 4.

What is the value of x when y = 8?​

Answer 1

If the variables y and x have a proportional relationship, we have

`xy=k`

Since (x,y)=(4,5) is a valid pair, we know that

`xy=20`

So, if y = 8, we have

`8x=20 \iff x=(20)/(8)=(5)/(2)`