## Which of the following points is closest to line $$y=x?$$

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### Which of the following points is closest to line $$y=x?$$

by Gmat_mission » Wed Sep 23, 2020 5:43 am

00:00

A

B

C

D

E

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Which of the following points is closest to line $$y=x?$$

A. $$(2, -1)$$
B. $$(2, 4)$$
C. $$(-1, 1)$$
D. $$(2, 1)$$
E. $$(-2, 0)$$

Source: GMAT Club Tests

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### Re: Which of the following points is closest to line $$y=x?$$

by Scott@TargetTestPrep » Mon Sep 28, 2020 12:31 pm
Gmat_mission wrote:
Wed Sep 23, 2020 5:43 am
Which of the following points is closest to line $$y=x?$$

A. $$(2, -1)$$
B. $$(2, 4)$$
C. $$(-1, 1)$$
D. $$(2, 1)$$
E. $$(-2, 0)$$

Source: GMAT Club Tests
Solution:

The best way to solve this problem is to draw the graph: Clearly, we see that (2, 1) is closest to the line y = x.

Alternate Solution:

Every ordered pair (x, y) on the line y = x has the difference |y - x| as 0. For example, the ordered pair (6, 6) is on the line y = x, and the difference |y - x| = |6 - 6| = 0.

For the given ordered pairs, the point with the smallest difference of |y - x| will be closest to the line y = x. We see that the point (2, 1) has a difference of |1 - 2| = |-1| = 1, and all the other ordered pairs have differences whose absolute values are greater than 1.