Straight Line and Pair of Straight Lines 1 Question 46
46. If $a, b$ and $c$ are in $AP$, then the straight line $a x+b y+c=0$ will always pass through a fixed point whose coordinates are (…) .
$(1984,2 M)$
Show Answer
Solution:
- Since, $a, b, c$ are in AP.
$$ \therefore \quad 2 b=a+c $$
or $\quad a-2 b+c=0$ which satisfy $a x+b y+c=0$
$\therefore a x+b y+c=0$ always pass through a fixed point $(1,-2)$.
