Activity question 6 (week 2)

[Neev Mehta]

Can someone explain why option 2 is incorrect? if m1*m2 = -1 then wont the 2 lines be perpendicular??

[Shubham Mittal]

It's mentioned that they make an cute and an obtuse angle. So, the lines are not perpendicular. So (m1*m2 not= -1).

[Ajay k Gupta]

Hello,sir / mam.

I also have the same confusion,

but according to me option a), c) and d) are wrong moreover as

there it is not mentioned that which of the angles or slopes are greater

and value of  acute angle θ and an obtuse angle ϕ will interchange accordingly for all the 3 options.

So it should be "tell incorrect options".

sir /mam if am going wrong anywhere please correct me...