Triangle Theorems
The interior angles of a triangle always sum to 180 degrees.
What is the triangle angle sum theorem?
If two triangles are congruent, then these must be congruent.
What are sides and angles?
This theorem state that if all three sides of two triangles are congruent, then the triangles are congruent.
What is SSS?
Rigid motions can be used to show that two shapes are ....
What is congruent?
A figure formed by line segments that join 3 non-collinear points.
What is a triangle?
If two sides of a triangle are congruent, the angles opposite of those sides are also congruent.
What is the isosceles triangle theorem?
If △PYL ≅ △XRN, this angle is congruent to ∠Y.
What is ∠R?
The number of theorems we have to prove triangle congruence.
What is five?
The points where the sides of a triangle intersect.
What are vertices?
A triangle is equilateral if and only if it is equiangular.
What is the equilateral triangles theorem?
If △PYL ≅ △XRN, this segment is congruent to segment PL.
What is segment XN?
The "H" and the "L" in the HL congruence theorem, refer to what parts of a right triangle?
What is hypotenuse and leg?
This rigid motion changes the orientation of an object by "spinning" it.
What is rotation?
The transformation that maintain and are used to prove congruence between two figures.
What are rigid motions?
An exterior angle of a triangle always equals the sum of the two non-adjacent interior angles.
What is the exterior angle theorem?
The acronym that is sometimes used for the definition of triangle congruence.
What is CPCTC?
To use the SAS congruence theorem, the angle that is congruent in two triangles must be this.
What is included?
What is inbetween the two sides?
A statement that tells which sides or angles of two triangles are congruent.
What is a congruence statement?
If two sides of a triangle or any polygon share a vertex, we would say that the sides are _______
What is adjacent?
If two angles in a triangle are congruent, the sides opposite of those angles must also be congruent.
What is the isosceles triangles theorem converse?
If △PYL ≅ △XRN, m∠Y = 30, m∠L = 110, then m∠X must be ...
What is 40 degrees?
What is 40?
Which two triangle congruence theorems require you to show that a pair of triangles have two congruent angles and one congruent side?
What are ASA and AAS?
Rigid motions do not change the _____ and _____ of a figure.
What is shape and size?
This property is used to argue that a shared side of two triangles are congruent, because the side is congruent to itself.
What is the reflexive property?