Show that the equation x^2+2xy+y^2-2x-2y-15=0
represents two parallel straight lines.
Show the equation
2012-09-23 11:54 pm
回答 (1)
2012-09-24 12:12 am
✔ 最佳答案
x² + 2xy + y² - 2x - 2y – 15 = 0(x + y)² - 2(x+ y) – 15 = 0(x + y – 5)(x + y + 3) = 0 x + y – 5 = 0 or x + y + 3 = 0 Since there’s no solution for these 2 equations, so x² + 2xy + y² - 2x - 2y – 15 = 0 represent 2 // lines.
參考: My Maths World
收錄日期: 2021-04-13 19:00:14
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