Slope of line A = (y2 - y1)/(x2 - x1) = 1
Product of slopes of two perpendicular lines = -1
This implies that the slope of line perpendicular to A = -1
Now, just use the above formula to find a slope which is NOT -1
Answer is D

It should be A)

@everything's eventual: I think your answer is correct and bravo!! for the effort. As we have to distribute 8 persons in 2 groups, No. of ways of doing that will be = 8C2.6C2 ways = 420 ways However, any given arrangement will repeat itself for both the teams e.g., Team 1 Team 2 (1,2) (3,4) (3,4) (1...

Two equally skilled teams play a four games tournament. What is the probability of the tournament ending at the fourth game with a winner?(Note : a team cannot win all the 4 games ) Here, we have 2 teams (equally skilled). So, the probability of win for each team is 1/2 for each game. Exhaustive se...

Thanks Kasia!
I thought you are saying the questions should also be negative. Bad inference

"Any" should be used only in negative sentences and questions. Therefore, the second sentence is incorrect @Kasia Well, I get the fact that usage of "any" in the mentioned question was wrong. But I am not able to understand what you imply by negative sentences and questions. Her...

I don't really know how E) is wrong. The possessive pronoun 'their' is referring to computer memory chips (so, no ambiguity). In fact, adding chips' circuits sounds too verbose and awkward (though not wrong).