Question

Four distinct points (2k, 3k), (1, 0), (0, 1) and (0, 0) lie on a circle for

• A. $\forall k\in I$
• B. K < 0
• C. 0 < k < 1
• D. For two values of k

Answer 1

The correct option is C 0 < k < 1

Find the equation of a circle passing through (0, 0), (1, 0), (0, 1)
Put (2K, 3K) in the equation, find K
$\Rightarrow x^2+y^2-x-y=0$ has $(2K,3K)\Rightarrow k=\frac{5}{13}$