Triangle Congruence
by Joshua Napper
1. Diliation
1.1. that creates a smaller image is called a reduction. A dilation stretches or shrinks the original figure.
2. Isometry
2.1. a linear transformation which preserves length
3. Rigid Transformation
3.1. is a transformation of the plane that preserves length
4. Acute Triangle
4.1. is a triangle with all three angles acute (less than 90°)
5. Equiangular Triangle
5.1. is a triangle where all three interior angles are equal in measure
6. triangle rigity
6.1. A property of triangles that states that if the side lengths of a triangle are fixed, the triangle can have only one shape.
7. CPCTC
7.1. "Corresponding parts of congruent triangles are congruent"
8. Right Triangle
8.1. Is a triangle that has at least one right angle
9. Obtuse Triangle
9.1. is a triangle in which one of the angles is an obtuse angle
10. Equilateral Triangle
10.1. is a triangle in which all three sides are equal
11. Isosceles Triangle
11.1. is a triangle with (at least) two equal sides
12. Scalene Triangle
12.1. is a triangle that has three unequal sides
13. auxiliary line
13.1. is an extra line needed to complete a proof in plane geometry
