Question

Suppose that y varies inversely with the square of x and y = 50 when x = 4. Find y when x = 5

Answer 1

y = 32.

Explanation:

y = k/x^2 where k is the constant of variation

When y = 50 x = 4, so

50 = k / (4)^2

f = 50 * 4^2 = 800.

So the relation is

y = 800/x^2

When x = 5

y = 800/5^2

= 32.