Acute triangle
A triangle that has three acute angles.
Acute Angle
An angle with a measure greater than 0° and less than 90°.
Angle
Two rays with a common endpoint form an angle.
Complementary Angles
Two angles are complimentary if the sum of their measures is 90°.
Congruent angles
Angles with the same measure.
Congruent figures
Figures that are the same shape and size.
Congruent segments
Line segments that are the same length.
Corresponding sides
The parts of congruent or similar figures that match.
Degree
The most common unit of measure for angles.
Equilateral triangle
A triangle having all three sides congruent and all three angles congruent.
Isosceles triangle
A triangle in which at least two sides are congruent.
Line segment
A straight path between two end points.
Obtuse angle
An angle that measures greater than 90° but less than 180°.
Obtuse triangle
A triangle having one obtuse angle.
Parallelagram
A quadrilateral pairs of opposite sides congruent and parallel.
Quadrilateral
A polygon with 4 sides
Rectangle
A quadrilateral with opposite sides congruent and parallel and all angles are right angles.
Rhombus
A parallelogram with all sides congruent.
Right angle
An angle that measures 90°
Right triangle
A triangle having one right angle
Scalene triangle
A triangle with no sides congruent
Side
A ray that is part of an angle
Similar figures
Figures that have same shape but different sizes.
Square
A Parallelogram with all sides congruent, all angles right angles, and opposite sides parallel.
