Question

40 POINTS!!!! Which sequence of transformations will result in an image that maps onto itself?

Answer 1

Answer:

Option C.

Step-by-step explanation:

Let a point (x, y) has a sequence of transformations,

Option A).

Reflects across x-axis then the coordinates will be,

(x, y) → (x, -y)

Then reflects across the y-axis,

(x, -y) → (-x, -y)

Image (x, y) gets changed to (-x, -y) therefore, point (x, y) doesn't map onto itself.

Option B).

(x, y) rotate 90° counter clockwise about the origin.

(x, y) → (-y, x)

Then reflect across x-axis,

(-y, x) → (y, x)

Since coordinates of the image and the actual are not same therefore, image doesn't map itself.

Option C).

(x, y) when reflected across x-axis,

(x, y) → (x, -y)

Then reflected over the x-axis,

(x, -y) → (x, y)

In this option point (x, y) maps onto itself after these transformations.

Option D).

(x, y) rotated 90°counterclockwise about the origin

(x, y) → (-y, x)

Then translated up by 2 units.

(-y, x) → (-y, x+2)

Therefore, (x, y) gets changed after these transformations and doesn't maps itself.

Option (C) will be the answer.