HMMT 十一月 2008 · GEN1 赛 · 第 7 题
HMMT November 2008 — GEN1 Round — Problem 7
题目详情
- [ 6 ] Find all ordered pairs ( x, y ) such that 2 2 ( x − 2 y ) + ( y − 1) = 0 .
解析
- [ 6 ] Find all ordered pairs ( x, y ) such that 2 2 ( x − 2 y ) + ( y − 1) = 0 . Answer: (2,1) The square of a real number is always at least 0, so to have equality we must have 2 2 ( x − 2 y ) = 0 and ( y − 1) = 0. Then y = 1 and x = 2 y = 2. 1