HMMT 二月 2007 · 几何 · 第 2 题
HMMT February 2007 — Geometry — Problem 2
题目详情
英文原题
- [ 3 ] A , B , C , and D are points on a circle, and segments AC and BD intersect at P , such that AP = 8,
P C = 1, and BD = 6. Find BP , given that BP < DP.
解析
英文解析
- [ 3 ] A , B , C , and D are points on a circle, and segments AC and BD intersect at P , such that AP = 8,
P C = 1, and BD = 6. Find BP , given that BP < DP.
Answer: 2 . Writing BP = x and P D = 6 − x , we have that BP < 3. Power of a point at P gives
AP · P C = BP · P D or 8 = x (6 − x ). This can be solved for x = 2 and x = 4, and we discard thelatter.