Math Chapter Wise The Line And General Equation Of Second Degree And Its Classification English MCQ OAVS TGT 2017 Q.Two lines with slopes m1 and m2 are perpendicular then, which of the following is true? Am1×m2 = 0 Bm1 = m2 C1 2 m –1 m = Dm1×m2 = –1 Show answer Correct answer: m1×m2 = –1