Reflections on the Coordinate Plane

Front

What is a reflection in geometry?

Back

A reflection is a transformation that flips a figure over a line, creating a mirror image.

Front

What is the line of reflection for a reflection across the x-axis?

Back

The x-axis itself is the line of reflection.

Front

What happens to the coordinates of a point (x, y) when it is reflected across the x-axis?

Back

The coordinates become (x, -y).

Front

What happens to the coordinates of a point (x, y) when it is reflected across the y-axis?

Back

The coordinates become (-x, y).

Front

If point A(2, 3) is reflected across the x-axis, what are the coordinates of A'?

Back

A' will be (2, -3).

Front

If point B(-4, 5) is reflected across the y-axis, what are the coordinates of B'?

Back

B' will be (4, 5).

Front

What is the algebraic representation of a reflection across the x-axis?

Back

The algebraic representation is (x, y) → (x, -y).

Front

What is the algebraic representation of a reflection across the y-axis?

Back

The algebraic representation is (x, y) → (-x, y).

Front

How do you reflect a triangle across the x-axis?

Back

You reflect each vertex of the triangle by changing the sign of the y-coordinate.

Front

If point C(3, -2) is reflected across the x-axis, what are the coordinates of C'?

Back

C' will be (3, 2).