Question

If y varies directly with x, and if y = 10 when x = 2, how do you find the direct variation equation?

Answer 1

Variation Eqn. is `y=5x.`

Explanation:

We know that `y prop x.`

`:. y=kx............(1),` where `k` is the constant of variation & `k!=0.`

Now to determine `k`, we use the given cond. that when `x=2, y=10`. Let us submit these resp. values in (1) to get, `10=2k,` or, `k=5.`

Letting `k=5` in (1), we get the Variation Eqn. as `y=5x.`

Answer 2

The direct variation equation is `y=5x`

Explanation:

`y prop x :. y = k*x ; y=10;` when `x=2 :. 10= k *2 or k =5` (k is constant of variation). Hence the variation equation is `y=5x`[Ans]