Question

The point (4, 1) is reflected over the line y=-x to create Point B. What are the coordinates of B?

(-1, -4)

(-1,4)

(1, -4)

(1,4)

Answer 1

(-1, -4)

Explanation:

y = -x is the 45° diagonal through the origin from top left to bottom right.

a reflection across that line brings anything that is in quadrant 1 (x and y are positive) to quadrant 3 (x and y are negative) like this point. and vice versa.

points in quadrant 2 stay in quadrant 2, points in quadrant 4 stay in quadrant 4.

but in every case x and y are exchanged and both signs are flipped like (-1, 2) turns into (-2, 1).

or for our point : (4, 1) turns into (-1, -4)