transformation

An operation that moves or changes a geometric figure in some way to produce a new figure

equilateral triangle

A triangle with three congruent sides

congruent

Figures where all parts of one figure are congruent to the corresponding parts of the other figure.

hypotenuse

The side opposite the right angle in a right triangle. It is the longest side.

reflection

A transformation that uses a line of reflection to create a mirror image of the original figure

rotation

A transformation that turns a figure about a fixed point called the center of rotation

scalene triangle

A triangle with no congruent sides.

acute triangle

A triangle with three acute angles

translation

A transformation that moves every point of a figure the same distance in the same direction

right triangle

A triangle with one right angle

vertex

The angle formed by the legs in an isosceles triangle

corollary

A statement that can be easily proven using a theorem

SSS

Postulate used to prove triangles are congruent if all 3 sets of corresponding sides are congruent.

SAS

Postulate used to prove triangles are congruent if 2 sets of corresponding sides and their included angles are congruent.

HL

Postulate used to prove right triangles are congruent if the hypotenuse and a leg of one right triangle are congruent to the corresponding parts of another right triangle