Question

Suppose y varies directly with x, and y=14 when x=-4. what is the value of y whan x=-6?

Answer 1

For x = -6, the value of y = 21

Explanation:

Here, y varies directly with x.

⇒ y ∝ x

⇒ y = k x for some k; where k = proportionality constant

CASE 1 : y = 14 when x = -4

⇒ 14 = k (-4)

or, k = 14/-4 = -7/2

⇒ k = -7/2

CASE 2 : when x = -6

Now,
`y = kx  = (-7)/(2)  * (-6)  = 21`

or, y = 21

Hence, for x = -6, the value of y = 21