The rule for a 90⁰ counterclockwise rotation about the origin is:
a) (x, y) → (-y, x)
b) (x, y) → (y, -x)
c) (x, y) → (-x, -y)
d) (x, y) → (x, -y)

Respuesta :

Answer:

a)(x,y)→ (-y, x)

Step-by-step explanation:

The answer is (a) (x, y) → (-y, x).

Here's why:

Counterclockwise Rotation: A 90-degree counterclockwise rotation means turning a point 90 degrees to the left around the origin.

Switching Coordinates: This rotation involves swapping the x and y coordinates, but also negating the new x-coordinate (which becomes the original y-coordinate).

Visualizing:

Imagine a point at (2, 3). Rotating it 90 degrees counterclockwise moves it to (-3, 2). The x-coordinate becomes -3, and the y-coordinate becomes 2.

Understanding the Other Options:

(b) (x, y) → (y, -x): This rule represents a 90-degree clockwise rotation.

(c) (x, y) → (-x, -y): This rule represents a 180-degree rotation (flipping the point across the origin).

(d) (x, y) → (x, -y): This rule reflects the point across the x-axis, not rotating it.