Term
|
Definition
| a closed plane figure formed from three or more segments such that each segment intersects exactly two other segments, one at each endpoint, and no two segments with a common endpoint are collinear |
|
|
Term
|
Definition
| a polygon in which any line segment that connects two vertices of the polygon passes only through the polygon’s interior |
|
|
Term
|
Definition
| a polygon in which at least one line segment that connects two vertices of the polygon passes through the polygon’s exterior (a polygon that is not convex) |
|
|
Term
|
Definition
| a polygon for which all interior angles have the same measure |
|
|
Term
|
Definition
| a polygon for which all segments have the same measure |
|
|
Term
|
Definition
| a polygon that is both equiangular and equilateral |
|
|
Term
| center (of a regular polygon) |
|
Definition
| the point that is equidistant from all vertices of a regular polygon |
|
|
Term
| central angle (of a regular polygon) |
|
Definition
| an angle whose vertex is the center of a regular polygon and whose sides pass through adjacent vertices of the polygon |
|
|
Term
| interior angle (of a polygon) |
|
Definition
| an angle whose vertex is a vertex of a polygon and whose two sides are defined by segments that share that vertex |
|
|
Term
| exterior angle (of a polygon) |
|
Definition
| an angle that forms a linear pair with an interior angle of a polygon |
|
|
Term
|
Definition
| two lines that intersect to form a right angle |
|
|
Term
|
Definition
| two coplanar lines that do not intersect |
|
|
Term
|
Definition
| the “steepness of a line,” which is calculated by dividing the change in the y-coordinate (often called “the rise”) by the change in the x-coordinate (often called “the run”) between any two points on the line; it represents the rate of change of the y value with respect to the x value |
|
|
Term
|
Definition
| the point on a segment that is equidistant from the segment’s two endpoints |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
| a part of a line that begins at one point and ends at another |
|
|
Term
|
Definition
| a part of a line that starts at a point and extends infinitely in one direction |
|
|
Term
|
Definition
| a figure formed by two rays with a common endpoint |
|
|
Term
|
Definition
| the point in common of the two rays that form an angle |
|
|
Term
|
Definition
| the region of a plane that falls between the two rays that form an angle (i.e., If two points, one from each side of an angle, are connected by a segment, the segment will pass through the __________ |
|
|
Term
|
Definition
| the portion of the plane containing an angle that is not in the angle's interior |
|
|
Term
|
Definition
| an angle whose measure is 90 degrees. |
|
|
Term
|
Definition
| an angle whose measure is less than 90 degrees. |
|
|
Term
|
Definition
| an angle whose measure is more than 90 degrees and less than 180 degrees |
|
|
Term
|
Definition
| an angle formed by two rays that go in opposite directions. This measures 180 degrees and is also known as a line! |
|
|
Term
|
Definition
| a pair of angles that share a side and form a line |
|
|
Term
|
Definition
| to have one or more points in common |
|
|
Term
|
Definition
| the set of all points that two geometric figures have in common |
|
|
Term
|
Definition
| a statement that is accepted as true without proof |
|
|
Term
|
Definition
| two coplanar angles that share a common vertex and a common side, but have no interior points in common |
|
|
Term
|
Definition
| the opposite angles formed by two intersecting lines |
|
|
Term
|
Definition
| two angles whose measures have a sum of 90 degrees |
|
|
Term
|
Definition
| two angles whose measures have a sum of 180 degrees |
|
|
Term
|
Definition
| a line that divides a segment into two congruent segments |
|
|
Term
|
Definition
| a segment bisector that is perpendicular to the segment that it bisects |
|
|
Term
|
Definition
| a line or ray through the vertex of an angle that divides the angle into two congruent angles |
|
|
Term
|
Definition
| a statement that you believe to be true. It is an “educated guess” based on observations. |
|
|
Term
|
Definition
| a convincing argument that uses logic to show that a statement must be true |
|
|
Term
|
Definition
| a statement that has been proven true using deductive reasoning |
|
|
Term
|
Definition
| a triangle for which one interior angle is a right angle |
|
|
Term
| hypotenuse (of a right triangle) |
|
Definition
| the side opposite the right angle in a right triangle |
|
|
Term
|
Definition
| the point where two sides (or edges) of a polygon intersect |
|
|
Term
|
Definition
| a segment connecting two non-adjacent vertices of a polygon |
|
|
Term
|
Definition
| a polygon with four sides |
|
|
Term
|
Definition
| a quadrilateral with one pair of parallel sides |
|
|
Term
|
Definition
| a quadrilateral with two pairs of parallel sides |
|
|
Term
|
Definition
| an equiangular quadrilateral |
|
|
Term
|
Definition
| an equilateral quadrilateral |
|
|
Term
|
Definition
|
|
Term
|
Definition
| a triangle with at least two congruent sides |
|
|
Term
| leg (of an isosceles triangle) |
|
Definition
| one of the two congruent sides of an isosceles triangle |
|
|
Term
| vertex angle (of an isosceles triangle) |
|
Definition
| the angle formed by the two legs of an isosceles triangle, or the angle opposite the base of an isosceles triangle |
|
|
Term
| base (of an isosceles triangle) |
|
Definition
| the side opposite the vertex angle of an isosceles triangle |
|
|
Term
| base angle (of an isosceles triangle) |
|
Definition
| an angle whose vertex is an endpoint of the base of an isosceles triangle, or an angle opposite one of the legs of an isosceles triangle |
|
|
Term
| leg (of a right triangle) |
|
Definition
| one of the sides of a right triangle that forms the right angle |
|
|
Term
|
Definition
| having the same size and shape |
|
|
Term
|
Definition
| a theorem that can be easily derived from another theorem |
|
|
Term
| alternate interior angles |
|
Definition
| two non-adjacent angles that lie in the interior of two lines cut by a transversal, but are on opposite sides of that transversal |
|
|
Term
| same-side interior angles |
|
Definition
| two angles that lie in the interior of two lines cut by a transversal and are on the same side of that transversal |
|
|
Term
|
Definition
a statement that can be written in the form “If p, then q,” where p is the hypothesis and q is the conclusion
Example: If a vehicle is a long board, then the vehicle has four wheels. |
|
|
Term
| hypothesis (of a conditional statement) |
|
Definition
| the clause following the words “if a(n)” in a conditional statement |
|
|
Term
| conclusion (of a conditional statement) |
|
Definition
| the clause following the words “then the” in a conditional statement |
|
|
Term
|
Definition
| A diagram composed of closed shapes used to illustrate the logical relationship among sets of objects. It is useful for illustrating conditional statements. |
|
|
Term
|
Definition
| an object that proves a conditional statement false. The object must fit the hypothesis but not the conclusion. |
|
|
Term
| converse (of a conditional statement) |
|
Definition
| a conditional statement formed by switching the hypothesis and conclusion of a conditional statement. An original statement “If p then q” becomes “If q then p” |
|
|
Term
| biconditional (statement) |
|
Definition
a conditional statement that is true both “forward” and “backward” and is written using “Iff” or “If and only if”
Example:
"A quadrilateral is a rectangle if and only if it has four right interior angles" or "Iff a quadrilateral is a rectangle, then it has four right interior angles." |
|
|
Term
| inverse (of a conditional statement) |
|
Definition
| a conditional statement formed by negating both the hypothesis and conclusion of a conditional statement. An original statement “If p then q” becomes “If not p then not q.” |
|
|
Term
| contrapositive (of a conditional statement) |
|
Definition
| a conditional statement formed by first negating both the hypothesis and conclusion of a conditional statement and then switching them. An original statement “If p then q” becomes “If not q then not p.” This form of a true conditional statement is always true. |
|
|
Term
|
Definition
| a right triangle whose acute angles have measures of 30° and 60°. It results from cutting an equilateral triangle in half. |
|
|
Term
|
Definition
| a right triangle whose acute angles each have a measure of 45°. It results from slicing a square in half along one of its diagonals. It is also referred to as an isosceles right triangle. |
|
|
Term
|
Definition
| a segment that stretches from one vertex of a triangle to the line containing the side opposite that vertex and that is perpendicular to that opposite side. |
|
|
Term
|
Definition
| the length of an altitude of a triangle |
|
|
Term
|
Definition
| a relationship between the squares of the lengths of the sides of a right triangle where a and b represent the lengths of the legs of the right triangle and c represents the length of the hypotenuse of the right triangle. The theorem states that a2 + b2 = c2 |
|
|
Term
|
Definition
| three natural numbers a, b and c that satisfy the Pythagorean theorem. That is a2 + b2= c2 |
|
|
Term
|
Definition
| a relationship between the squares of the lengths of the sides of a triangle, where a and b represent the lengths of the shorter sides of the triangle and c represents the length of the longest side of the triangle. There are three cases: a2 + b2 = c2, which indicates a right triangle; a2 + b2 < c2 , which indicates an obtuse triangle; and a2 + b2 > c2, which indicates an acute triangle |
|
|
Term
|
Definition
| the number of non-overlapping unit squares of a given size that will exactly cover the interior of a figure |
|
|
Term
|
Definition
| the distance around a closed, plane figure |
|
|
