Triangle Transformations and Congruence

The lesson covers composing figures using triangles, focusing on rigid transformations like reflections and rotations. It explains how these transformations maintain congruent angles and side lengths, using isosceles triangles and parallelograms as examples. The lesson concludes with practice problems involving triangle transformations.

What is a key characteristic of an isosceles triangle?

• All angles are different.

• It has two sides of equal length.

• It has no equal sides.

• All sides are of different lengths.

What happens to the angles of a triangle when it is reflected over a line?

• The angles remain the same.

• The angles change.

• The angles become smaller.

• The angles become larger.

What shape is formed when a triangle is rotated 180° around its midpoint?

• A square

• A parallelogram

• A circle

• A rectangle

When rotating a triangle around a midpoint, what remains unchanged?

• The color of the triangle

• The side lengths and angles

• The position of the triangle

• The size of the triangle

What is the result of applying a sequence of rigid transformations to a triangle?

• The triangle becomes smaller.

• The triangle changes shape.

• The triangle becomes larger.

• The triangle remains congruent.

How can you verify that two triangles are congruent after a transformation?

• By comparing their positions

• By measuring their side lengths and angles

• By observing their orientation

• By checking if they have the same color

What is the purpose of using a ruler in the exercises involving triangles?

• To draw straight lines

• To erase mistakes

• To measure side lengths accurately

• To color the triangles

What is a rigid transformation?

• A transformation that changes the size of a shape

• A transformation that alters the color of a shape

• A transformation that rotates a shape randomly

• A transformation that preserves the size and shape

What is the final position of point A after a series of transformations?

• (-1, -6)

• (1, 1)

• (3, 4)

• (0, 0)

What is the main takeaway from the lesson on rigid transformations?

• Rigid transformations are not useful.

• Rigid transformations are only for triangles.

• Rigid transformations preserve congruence.

• Rigid transformations change the shape of figures.