Q209 / 270 · NDA 2021 (Phase 1) · Mathematics
If $A, B$ and $C$ are in AP , then the straight line $A x+2 B y+C=0$ will always pass through a fixed point. The fixed point is
- A$(0,0)$
- B$(-1,1)$
- C$(1,-2)$
- Correct answerD$(1,-1)$
Solution
As $A, B$ and $C$ are in A.P.
$\therefore 2 B=A+C \Rightarrow A-2 B+C=0$
From given equation $A x+2 B y+C=0$.
For $(x, y)=(1,-1), A-2 B+C=0$
Hence, line always passes through $(1,-1)$.
Hence, the correct answer is option: 'D'.