Published by K12 Handhelds, Inc.

Portal, AZ

www.k12handhelds.com

Copyright © 2008 by K12 Handhelds, Inc. License CC-by,

This work is licensed under a Creative Commons Attribution 3.0 United States License.

Developed in conjunction with Wayne Township School System.

**acute angle** – an angle that is less than 90°

An acute angle is smaller than a perfectly square corner.

**acute triangle** – a triangle with three acute angles

**adjacent angles** – two angles that share a vertex (the point where two sides meet) and a common side

**angle of rotation** – when rotating a shape, the angle and direction of rotation

The direction is given as clockwise or counter-clockwise.

**center of rotation** – the fixed point a figure is rotated around

**complementary angles** – two angles that have a sum of 90°

**congruent angles** – two angles that have the same measurement

**congruent polygons** – polygons that have the same shape and the same size

**congruent sides** – sides that are the same length

**corresponding angles** – two congruent angles on the same side of a line that crosses two parallel lines

**equilateral triangle** – a triangle with three congruent sides

**heptagon** – a polygon with seven sides

**hexagon** – a polygon with six sides

**image** – the new figure or shape formed after a transformation

**intersecting lines** – two lines that meet at a point

**isosceles triangle** – a triangle with two congruent sides

**line of reflection** – the line a shape is reflected or flipped over

**line of symmetry** – the line that divides something with line symmetry

**line symmetry** – when a figure or shape can be divided by a line so that the part on each side is a mirror image of the part on the other side

**obtuse angle** – an angle that is more than 90° but less than 180°

An obtuse angle is bigger than a perfectly square corner, but smaller than a straight line.

**obtuse triangle** – a triangle with one obtuse angle

**octagon** – a polygon with eight sides

**parallel lines** – two lines in the same plane that are the same distance apart at all points and never meet

**parallelogram** – a quadrilateral with two pairs of parallel sides

**pentagon** – a polygon with five sides

**perpendicular lines** – two lines that meet to form four right angles

**plane** – a flat surface that extends in all directions without end

**polygon** – a closed plane figure made of connected line segments

Triangles, squares, and rectangles are examples of polygons. They are all closed shapes.

**quadrilateral** – a polygon with four sides

**reflection** – a flip; a way of moving a shape across a line, producing a mirror image, like flipping a pancake

**regular polygon** – a polygon with all congruent sides and all equal angles

**rhombus** – a parallelogram with four congruent sides

**right angle** – an angle that is exactly 90°

A right angle makes a perfectly square corner.

**right triangle** – a triangle with one right angle

**rotation** – a turn; turning or spinning a shape, like a doing a cartwheel

**rotational symmetry** – when a figure is turned 180° or less and produces a figure that is identical

**scalene triangle** – a triangle with no congruent sides

**similar polygons** – polygons that have the same shape but different sizes

**straight angle** – an angle that is exactly 180°

A straight angle makes a perfectly straight line.

**supplementary angles** – two angles that have a sum of 180°

**transformation** – a movement of a shape on a plane; a change in a shape; a way of mapping the shape onto another space

Examples of transformations are translations, reflections, and rotations.

**translation** – a slide; moving a shape along a line or scooting it over

**trapezoid** – a quadrilateral with one pair of parallel sides

**vertical angles** – the opposite angles formed when two lines cross

Vertical angles are always congruent angles. They have the same measurement.

1. Match the type of angle with its picture.

**Check the box or boxes that describe each set of angles. There may be more than one correct answer.**

6. What are two lines that never meet called?

A) __plane__
B)

7. What are two lines that meet to form four right angles called?

A) __parallel__
B)

8. What is a flat surface that extends with no end?

A) __plane__
B)

9. Which two angles are corresponding?

A) __B and D__
B)

10. Which two angles are vertical?

A) __A and B__
B)

11. Which two angles are supplementary?

A) __C and D__
B)

Match the polygon with its name.

25. These two polygons are ___.

A) __regular__
B)

26. These two polygons are ___.

A) __regular__
B)

27. These two polygons are ___.

A) __regular__
B)

28. The transformation shown here is a ___.

A) __translation__
B)

29. The transformation shown here is a ___.

A) __translation__
B)

30. The transformation shown here is a ___.

A) __translation__
B)

31. What is the angle of rotation in this rotation?

A) __90° counter-clockwise__
B)

32. What is the angle of rotation in this rotation?

A) __90° counter-clockwise__
B)

33. What is the angle of rotation in this rotation?

A) __45° counter-clockwise__
B)

34. Does this figure have line symmetry?

35. Does this figure have line symmetry?

36. Does this figure have line symmetry?

37. Does this figure have line symmetry?

38. Does this figure have rotational symmetry?

39. Does this figure have rotational symmetry?

40. Does this figure have rotational symmetry?

41. Does this figure have rotational symmetry?