Question

What are the coordinates of polygon JKLM with the vertices at J(-1,4), K(2,5), L(5,2), and M(4,-1) after it is reflected over the y=x?

Answer 1

The polygons will have its vertices after a reflection over the y=x will be:

• J'(4, -1)

• K'(5, 2)

• L'(2, 5)

• M'(-1, 4)

Explanation:

We know that when we reflect a point across the line y = x, the x-coordinate, and y-coordinate tend to replace their places.

i.e.

The reflection of the point (x,y) across the line y = x is the point (y, x).

P(x, y) = P'(y, x)

Given the points before the a refecltion over y=x

• J(-1, 4)

• K(2, 5)

• L(5, 2)

• M(4, -1)

Thus, the coordinates after the polygon are reflected over the y=x will be:

P(x, y) = P'(y, x)

J(-1, 4) = J'(4, -1)

K(2, 5) = K'(5, 2)

L(5, 2) = L'(2, 5)

M(4, -1) = M'(-1, 4)

Therefore, the polygons will have its vertices after a reflection over the y=x will be:

• J'(4, -1)

• K'(5, 2)

• L'(2, 5)

• M'(-1, 4)