2023 AMC 8 Problem 7

Below is the video solution and professionally curated solution for Problem 7 of the 2023 AMC 8, from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 2023 AMC 8 solutions, or check the answer key.

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Concepts:coordinate geometrylinear equation

Difficulty rating: 1070

7.

A rectangle, with sides parallel to the xx-axis and yy-axis, has opposite vertices located at (15,3)(15, 3) and (16,5).(16, 5). A line is drawn through points A(0,0)A(0, 0) and B(3,1).B(3, 1). Another line is drawn through points C(0,10)C(0, 10) and D(2,9).D(2, 9). How many points on the rectangle lie on at least one of the two lines?

00

11

22

33

44

Video solution:
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Written solution:

We can graph the two lines.

From this, we see that only the top left corner of the rectangle intersects either line.

Thus, B is the correct answer.

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