Q51 / 160 · WBJEE 2011 · Mathematics
If the three points \(A(1,6), B(3,-4)\) and \(C(x, y)\) are collinear then the equation satisfying by \(x\) and \(y\) is
- Correct answerA\(5 x+y-11=0\)
- B\(5 x+13 y+5=0\)
- C\(5 x-13 y+5=0\)
- D\(13 x-5 y+5=0\)
Solution
\(\begin{aligned}
& \text {Hints: }\left|\begin{array}{ccc}
1 & 1 & 6 \\
1 & 3 & -4 \\
1 & x & y
\end{array}\right|=0 \\
& \Rightarrow 1(3 y+4 x)-(y-6 x)+1(-4-18)=0 \Rightarrow 3 y+4 x-y+6 x-12=0 \\
& \Rightarrow 2 y+10 x-22=0 \\
& y+5 x=11
\end{aligned}\)
Hence, the correct answer is option: 'A'.