1. What is a plane shape?

Plane shapes are flat shapes such as rectangles and circles.

Solid objects such as spheres and prisms exist in three dimensions.

2. What do the short lines on the sides of shapes indicate?

The lines show that sides are the same size.

Arrows on the sides of shapes indicate that lines are parallel.

In a vector diagram an arrow indicates the direction of the vector.

3. What is a regular polygon?

A regular polygon is one with equal sides and angles.

4. What is the difference between a pair of similar triangles and a pair of congruent triangles?

A pair of similar triangles are the same shape, that is they have the same angles, but can be different sizes.

A pair of congruent triangle are the same shape and the same size.

5. Are congruent shapes also similar?