If (y propto frac{1}{x^2}) and x = 3 when y = 4, find y when x = 2.
- A.
1 - B.
3 - C.
9 - D.
18 - E.
21
Correct Answer: Option C
Explanation
(y propto frac{1}{x^2})
(y = frac{k}{x^2})
(4 = frac{k}{3^2})
(k = 4 times 3^2 = 36)
(y = frac{36}{x^2})
When x = 2,
(y = frac{36}{2^2} = 9)