1. Congruent Polygons – Polygons with the same shape and size
2. Side-Side-Side – Proves how triangles are congruent. Three pairs of
corresponding sides of a triangle are congruent
3. Side-Angle-Side – Proves how triangles are congruent. One set of
corresponding sides are congruent, followed by a set of corresponding
angles, followed by another set of corresponding sides
4. Angle-Side-Angle – Proves how triangles are congruent. One set of
corresponding angles are congruent, followed by a set of corresponding
sides, followed by another set of corresponding angles
5. Acute Triangle – A triangle with three acute angles
6. Obtuse Triangle – A triangle with one obtuse angle
7. Right Triangle – A triangle with one right angle
8. Equilateral Triangle – A triangle with three congruent sides
9. Isosceles Triangle – A triangle that has at least two congruent sides
10.Scalene Triangle – A triangle with no congruent sides
11.Quadrilateral – A polygon with 4 sides
12.Parallelogram – A quadrilateral with both pairs of opposite sides parallel
13.Trapezoid – A quadrilateral with exactly one pair of parallel sides
14.Rhombus – A quadrilateral with both pairs of opposite sides parallel and
four congruent sides.
15.Rectangle – A quadrilateral with both pairs of opposite sides parallel and
four right angles
16.Square – A quadrilateral with pairs of opposite sides parallel, four
congruent sides, and four right angles.
17.Regular Polygon – A polygon with all sides congruent and all angles
congruent
18.
Polygon Angle Sum – For a polygon with n sides, the sum of the measures
of the interior angles is (n – 2)180O
19.Circumference – The distance around the circle
20.Radius – A segment that has one endpoint at the center of the circle and
the other endpoint on the circle
21.Chord – A segment with endpoints on the circle
22.Diameter – A special chord that passes through the center of a circle
23.Solids – or 3D figures, are objects that do not lie in a plane. They have
length, width, and height.
24.Prism – Has 2 parallel bases that are congruent polygons. The lateral faces
are parallelograms
25.Pyramid – Has exactly one base, which is a polygon. The lateral faces are
triangles
26.Cylinder – Has two bases that are parallel, congruent circles
27.Cone – has exactly one circular base and one vertex
28.Polyhedron – A solid with a polygon for each face
29.Skew Lines – Lines that do not intersect and are not parallel. Unlike a pair
of parallel lines or a pair of intersecting lines, skew lines do not lie in the
same plane
30.Lateral Face – The faces that join the bases of a solid
31.Lateral Edge – The edges that form the lateral faces of a solid
32.Surface Area – Of a solid figure is the sum of the areas of its surfaces. The
area of its net
33.Lateral Area –The sum of the areas of the lateral surfaces of a solid
34.Slant Height – The height of a pyramids lateral faces indicated by the
symbol ℓ
35.Volume – The number of unit cubes needed to fill a solid
36.Adjacent Angles – Have a common vertex a common side, but no common
interior points
37.Vertical Angles – Formed by two intersecting lines and are opposite each
other
38.Supplementary Angles – The sum of 2 angles = 180 degrees
39.Complementary Angles – The sum of 2 angles = 90 degrees
40.Perpendicular Lines – Two lines that intersect to form a right angle
41.Transversal – A line that intersects two other lines at different points
42.Corresponding Angles – Lie on the same side of the transversal and are in
corresponding positions
43.Alternate Interior Angles – Lie within a pair of lines and on opposite sides
of the transversal
44.Dilation – A transformation in which a figure and its image are similar
45.Scale Factor – The ratio of a length in the image to the corresponding
length in the original figure
46.Enlargement – A dilation with a scale factor greater than one
47.Reduction – A dilation with a scale factor less than one
48.Rotation – Is a transformation that turns a figure about a fixed point
49.Center of Rotation – Is a fixed point about which a figure is rotated
50.Angle of Rotation – Is the number of degrees that a figure rotates
51.Rotational Symmetry – A figure that can be rotated 180 degrees or less and
match the original figure
52.Transformation – A change in the position, shape, or size of a figure
53.Translation (slide) – Is a transformation that moves each point of a figure
the same distance and in the same direction
54.Image – The figure you get after a transformation. We use "prime" notation
to name it
55.Line of Symmetry – When one side of a figure is the mirror image of the
other side
56.Reflectional Symmetry – When a figure can be reflected over a line so that
its image matches the original figure
57.Line of Reflection – A line across which a figure is reflected
58.Reflection – A transformation that flips a figure over a line