2003 AMC 10B Problem 11

Below is the professionally curated solution for Problem 11 of the 2003 AMC 10B, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2003 AMC 10B solutions, or check the answer key.

All of the real AMC 8, AMC 10, AMC 12, and AIME problems in our complete solution collection are used with official legal permission of the Mathematical Association of America (MAA).

Concepts:coordinate geometryslopelinear equation

Difficulty rating: 1240

11.

A line with slope 33 intersects a line with slope 55 at the point (10,15).(10, 15). What is the distance between the xx-intercepts of these two lines?

22

55

77

1212

2020

Solution:

The lines are y15=3(x10)y-15=3(x-10) and y15=5(x10).y-15=5(x-10).

Setting y=0y=0 gives xx-intercepts x=5x=5 and x=7.x=7. The distance between (5,0)(5,0) and (7,0)(7,0) is 2.2.

Thus, the correct answer is A.

Problem 11 in Other Years