Question

The family of straight lines $3(a+1)x-4(a-1)y+3(a+1)=0$ for different values of a passes through a fixed point whose coordinates are

• A. $(1,0)$
• B. $(-1,0)$
• C. $(-1,-1)$
• D. None of these

Answer 1

The correct option is B $(-1,0)$

Family of straight lines

$3(a+1)x-4(a+1)y+3(a+1)=0$

$\Rightarrow (3x+4y+3)+a(3x-4y+3)=0$

$3x+4y+3=0$

$3x-4y+3=0$

$\therefore 6x+6=0$

$\Rightarrow x=-1$

$\therefore y=0$

$\therefore$ coordinates of fixed point :$(-1,0)$ Ans.