Triangles
Three equal sides. Three equal angles, always 60°
Equilateral Triangle
Extends in both directions without end (infinitely).
Line(s)
An internal angle which is equal to 90°
Right Angle
_________ Angles have the same angle. That is all. The term comes from Latin congruere, "to agree". So the angles "agree".
Congruent angles
Shapes that have the same size, area, angles and line lengths are known as...
Congruent
All angles are less than 90°
Acute Triangle
When a line does have ends it is called...
A line segment
More than 90° but less than 180°
Obtuse Angle
These two angles (140° and 40°) are ___________ angles, because they add up to 180°
Supplementary
If two figures have the same shape, but are different sizes, then they are...
Similar
Two equal sides. Two equal angles.
Isosceles Triangle
When a line has just one end it is called...
A ray
Sometimes people say "You did a complete 180 on that!" ... meaning you completely changed your mind, idea or direction. What type of angle is this a reference to?
A straight angle
These two angles (40° and 50°) are __________ angles, because they add up to 90°
Complementary
_____________ means that we have two triangles with all three sides equal, and are therefore congruent.
SSS or "side, side, side"
Has an angle more than 90°
Obtuse Triangle
Always the same distance apart and will never meet.
Parallel Lines
This type of angle is more than 180° but less than 360°
A reflex angle
Two angles are __________ when they have a common side and a common vertex (corner point) and don't overlap.
Adjacent
______________ means that we have two triangles where we know two sides and the included angle are equal, therefore making the triangles congruent.
SAS or "side, angle, side"
No equal sides. No equal angles.
Scalene Triangle
Lines that are at right angles (90°) to each other.
Perpendicular Lines
A full rotation is _____ degrees
360°
A ___________ is a line that crosses at least two other lines.
Transversal
___________ means that we have two triangles where we know two angles and the included side are equal.
ASA or "angle, side, angle"