Which of the following pair of straight lines intersect at right angle?

Options

A. `2x^(2)=y(x+2y)`
B. `(x+y)^(2)=x(y+3x)`
C. `2y(x+y)=xy`
D. `y=+-2x`

Answer

A

Explanation

`2x^(2)-2y^(2)-xy=0`
Here, `a=2,b=-2`
and `h=-(1)/(2)`
Now, `a+b=2-2=0`
Hence, pair of lines intersect at right angles.