【正确答案】 A

【答案解析】Use TACTIC 5: don't calculate either slope. Quickly, make a rough sketch of line k, going through (1,1) and (5,2), and draw line m perpendicular to it. [*] Line k has a positive slope (it slopes upward), whereas line m has a negative slope (it slopes downward). Quantity A is greater. [Note: The slope of k is [*] and the slope of m is -4, but you don't need to calculate either one. See Section 11-N for all the facts you need to know about slopes.] **If you don't know this fact about slopes, use TACTIC 6. The answer cannot be Choice D, and if two lines intersect, their slopes cannot be equal, so eliminate Choice C. Guess Choice A or B.