7.1-7.2Transformations and Symmetry

Front

What is a translation in geometry?

Back

A translation is a type of transformation that moves every point of a shape the same distance in a specified direction.

Front

What is the rule for translating a point (x, y) by (a, b)?

Back

The rule is (x, y) → (x + a, y + b).

Front

If a triangle is translated by the rule (x + 2, y - 1), what happens to the coordinates of its vertices?

Back

Each vertex's x-coordinate increases by 2 and the y-coordinate decreases by 1.

Front

What does the notation (x, y) → (y, -x) represent?

Back

This notation represents a rotation transformation that swaps the x and y coordinates and changes the sign of the new x-coordinate.

Front

How do you determine the number of lines of symmetry in a shape?

Back

Count the number of ways you can divide the shape into two identical halves by a line.

Front

What is a line of symmetry?

Back

A line of symmetry is a line that divides a shape into two mirror-image halves.

Front

What is the difference between reflection and rotation?

Back

Reflection flips a shape over a line, while rotation turns a shape around a fixed point.

Front

What is the effect of a 90-degree rotation on the coordinates of a point (x, y)?

Back

The new coordinates will be (-y, x).

Front

What is the transformation rule for a reflection over the x-axis?

Back

The rule is (x, y) → (x, -y).

Front

What is the transformation rule for a reflection over the y-axis?

Back

The rule is (x, y) → (-x, y).