Q86. The general second-degree equation ax2 + 2hxy + by2 + 2gx + 2fy + c = 0 represents a pair of straight lines if:Mathematics — NUST Mock 5 — Question 86 of 200A. h2 - ab > 0B. a + b = 0C. abc + 2fgh - af2 - bg2 - ch2 = 0D. h2 = abPractice more Mathematics MCQs for entrance exam preparation on Examora.io.← Previous Question Next Question →