Question

The equation of the line parallel to the line joining $(4,2)$ and $(2,4)$ and whose $y$-intercept is $4$ units along positive $y$- axis is

• A. $y+x-4=0$
• B. $y+x+4=0$
• C. $x-y+4=0$
• D. $2x+y=0$

Answer 1

The correct option is A $y+x-4=0$

Slope of line joining $(4,2)$ and $(2,4)$
$=\frac{4-2}{2-4}=\frac{2}{-2}=-1$
As the required line is parallel to the above line so,
slope of required line $=m=-1$
$y$ intercept $=c=4$
Hence equation of line is $y=mx+c$
$y=-x+4$
$\Rightarrow y+x-4=0$