《2026年天利38套中考试题精选英语成都专版》

B
Hi Peter,
I learned something amazing today. It's about solving a real - life problem! Let me share it with you.
The problem:
Wang Ming, a 9th - grade student, goes to school (point B) from his house (point A). On his way to school, he walks quickly to the Food Street for his breakfast. Look at the map of his neighborhood, in order not to be late for school, which breakfast house (point P) should he choose along the street (AP + PB) to shorten his total walking distance?
| House A | School B |
| --- | --- |
| | |
| Food Street | |
| A' | |
| Map of Wang Ming's Neighborhood | |
Actually, this is called Heron's Shortest Path (路径) Problem, named after a Greek math expert who studied light reflection 2 000 years ago! He discovered light always takes the shortest path when reflecting off a mirror. For Wang Ming's problem, the street acts like a "mirror".
How it works:
①Mirror Trick: Imagine reflecting point A across the street to create a "mirror image" A'. Now, A' is on the opposite side of the street, exactly as far from the street as A.
②The Straight Line between two points is the Shortest Path! Connect A' and B. Where this line crosses the street is the best point P!
Why it works:
—By reflecting A to A', the distance AP + PB becomes A'P + PB (since AP = A'P).
—The straight line A'B is the smallest possible total distance.
Cool, Right?
It's amazing how the math expert from ancient Greece solves a real problem in life! His idea is even used today in GPS systems and building design.
Now, let's look back at Wang Ming's problem. If both Wang Ming's house (point A) and the school (point B) are 2 km away from the street, and it's 3 km from Wang's house to the school. What's the shortest path of AP + PB?
Let me know your answer! I'm looking forward to your reply!
Yours,
Li Hua

71. What does Li Hua mainly talk about?
A. How to use math to solve real - life problems.
B. How to find breakfast houses quickly.
C. How the light reflects off the mirror.
72. What did Heron study 2 000 years ago?
A. Light reflection.
B. Mirror trick.
C. Building design.
73. What does the straight line between A' and B show?
A. The actual path of light.
B. The correct location back home.
C. The best choice of a breakfast house for Wang Ming.
74. If you were Peter, what would be your answer?
A. 3 km.
B. 5 km.
C. 7 km.
75. Which problem is solved by Heron's Shortest Path Problem?

A B C

答案： 71.A 72.A 73.C 74.B 75.C