Geometry Vocab
Caroline Thuet
Period 3
Mr. Palafox
AA Similarity
(angle angle similarity)
In two triangles, if two pairs of corresponding angles are congruent, then the triangles are similar.
Adjacent
adjoining
Altitude
The perpendicular distance from the vertex of a figure to the side opposite the vertex.
Ambiguous case of the Law of Sines
If you are given two angles and one side (ASA or AAS), the law of sines will nicely provide you with ONE solution for a missing side.
Angle Bisector
An angle bisector is a line that divides an angle in half.
Angle of Rotation
Angle formed when rays are drawn from center of rotation to a point and its image
Between
When something is in or not directly in the middle of two points
Bisect(or)
To divide into two congruent parts
Center of Dilation
A transformation that grows or shrinks a polygon by a given proportion about a center point.
Center of Rotation
In a rotation, the point that does not move. The rest of the plane rotates around this one fixed point.
Collinear
Points on the same line
Congruent
The same
Contraction
A shrinking of an object.
Consecutive Angles
The pair of angles on one side of the transversal but inside the two lines are called Consecutive Angles.
Coplanar
Points on the same plane
Corresponding Sides
If the relative position of two sides in same in two figures, then they are called corresponding sides.
Cosine
(in a right triangle) the ratio of the side adjacent to a given angle to the hypotenuse.
Dilation
To expand or cause to expand.
Diagonals
Connecting two nonadjacent angles or vertices of a polygon or polyhedron, as a straight line.
Distance Formula
If A(x, y,) and B(x,y,) are points, then the distance between A and B is
Endpoint
line segments
Equilateral
Having all sides equal.
Equiangular
Having all the angles equal.
Expansion
Expanding, dilating, and growing something.
Function
A relation between two sets in which one element of the second set is assigned to each element of the first set, as the expression y=x2
Geometric Mean
The mean of n positive numbers obtained by taking the n th root of the product of numbers.
Hypotenuse
The side of the right triangle opposite the right triangle.
Image
The new figure on the plane after transformations
Intersection of Lines
Set of points that two or more geometric figures have in common
Isometry
A transformation that preserves lengths
Kite
A quadrilateral whose four sides can be grouped into two pairs of equal-length sides that are adjacent to each other.
Law of Cosines
A law stating that the square of a side of a plane triangle is equal to the sum of the squares of the other two sides minus twice the product of the other sides multiplied by the cosine of the angle between them.
Law of Sine
A law stating that the ratio of a side of a plane triangle to the sine of the opposite angle is the same for all three sides.
Length
the distance between some thing
Line
has toe arrowheads, extends straight
Line of Symmetry
If you can reflect (or flip) a figure over a line and the figure appears unchanged, then the figure has reflection symmetry or line symmetry.
Line Segment
Two points, or end points that stop the line
Mapping
A function
Median
A straight line from a vertex of a triangle to the midpoint of the opposite side.
Midpoint
the point that cuts a segment into pieces
Midpoint Formula
A(x,y) B(x2, y2)
the the midpoint it
Opposite
Situated, placed, or lying face to face with something else or in corresponding positions with relation to an intervening line, space, or thing.
Opposite Angles
When two lines intersect, four angles are formed. The angles that are directly opposite to each other are called opposite angles.
Opposite Ray
If C is between A and B, then CA and CB are opposite rays
Parallelogram
A Quadrilateral having both pairs of opposite sides parallel to each other
Perpendicular Bisector
Is a special kind of segment, ray, or line that intersects a given segments at a 90 degree angle.
Plane
It extends continually even though it looks as though it has edges
Point
No dimension
Pre-image
The original figure on a plane
Proportion
Dimensions of a size.
Pythagorean Theorem
the theorem that the square of the hypotenuse of a right triangle is equal to the sum of the squares of the other two sides.
Quadrilateral
Having Four sides
Ratio
The relation between two similar magnitudes with respect to the number of times the first contains the second: the ratio of 5 to 2, written 5:2, or 5/2
Rectangle
A parallelogram having four right angles.
Reflection
The act of reflecting a triangle across the axis.
Reflectional Symmetry
Causes the other half to look the opposite of the other half, the same distance away.
Regular Polygon
A polygon with all sides and angles equal.
Rhombus
An oblique-angled equilateral parallelogram; any equilateral parallelogram except a square.
Rotation
A type of transformation in which is turned called center of rotation
Scale Factor
A number used as a multiplier in scaling.
Segment Bisector
A segment ray or line, or plane that intersects at midpoint
Similar Figures
The ratio between the areas of similar figures is equal to the square of the ratio of corresponding lengths of those figures.
Sine
The trigonometric function that for an acute angle is the ratio between the leg opposite the angle when it is considered part of a right triangle and the hypotenuse.
Solve a triangle
Square
A rectangle having all four sides with equal length.
Symmetry
A geometrical or other regularity that is possessed by a mathematical object and is characterized by the operation that leaves the object invariant.
Supplementary
Either of the two angles that added together produce an angle of 180
Tangent
Meeting a curve or surface in a single point if a sufficiently small interval is considered.
Trapezoid
A quadrilateral with two parallel and two non parallel sides.
Transformation
operation that moves a preimage onto an image
Translation
Maps every two points on a plane
Trigonometric Ratios
It is a branch of mathematics that studies relationships involving lengths and angles of triangles.
Vector
A quantity possessing both magnitude and direction, represented by an arrow the direction of which indicates the direction of the quantity and the length of which is proportional to the magnitude.