Question

Ex.) y varies inversely with x. If x = -2 when y = -8, find y when x = -4.

Answer 1

y = -4

Explanation:

Since x and y vary inversely, we have:

xy=k

For x= -2 and y = -8, we have:

⇒ -2×-8=k

⇒ k= 16

For x= -4, we have :

⇒ -4y=16

⇒ y= 16/-4

⇒ y= -4

[RevyBreeze]

Answer 2

y = -4

Explanation:

The equation for inverse variation is

xy = k where k is a constant

x=-2 and y = -8 so we can find k

-2 * -8 = k

16 = k

The equation is xy = 16

Know we want to find y when x = -4

-4 *y =16

Divide each side by -4

-4y /-4 = 16/-4

y = -4