Geometry Semester Review Topic 2

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

How do you find the coordinates of a reflection across a vertical line, such as x = 3?

Back

To find the reflection of a point (x, y) across x = 3, use the formula: (2*3 - x, y).

Front

What is the result of reflecting the point (1, 4) across the line x = 3?

Back

The reflected point is (5, 4).

Front

What does the transformation (x, y) → (x + 7, y - 3) represent?

Back

This transformation represents a translation, moving the point 7 units to the right and 3 units down.

Front

How do you apply a translation to the point (1, -1) using the transformation (x, y) → (x + 7, y - 3)?

Back

The new coordinates are (1 + 7, -1 - 3) = (8, -4).

Front

What is a 180° rotation about the origin?

Back

A 180° rotation about the origin transforms a point (x, y) to (-x, -y).

Front

What are the new coordinates of the point (6, -1) after a 180° rotation about the origin?

Back

The new coordinates are (-6, 1).

Front

What is dilation in geometry?

Back

Dilation is a transformation that changes the size of a figure but not its shape, using a scale factor.

Front

How do you dilate a point (x, y) using a scale factor of k?

Back

The new coordinates after dilation are (kx, ky).

Front

What are the new coordinates of the point (-3, 0) after dilation with a scale factor of k = ⅓?

Back

The new coordinates are (-1, 0).