point
- an exact location in space(#1)
line
- an endless collection of points along a straight path(#2)
line segment
- part of a line that has two endpoints(#3)
ray
- part of a line that has one endpoint and extends endlessly in the other direction (#4)
plane
- an endless flat surface that is named by any three points NOT on the same line (#5)
intersecting lines
- two lines that cross at exactly one point(#6)
parallel lines
- lines in the same plane that stay exactly the same distance apart(#7)
perpendicular lines
- two lines that intersect to form right angles(#8)
angle
- a figure formed by two rays that meet at a common endpoint(#9)
vertex
- the point at which 2 rays of an angle or 2 sides of a polygon meet(#10)
side
- the line segments that form a polygon(#11)
degree
- a unit for measuring angles(#12)
right angle
- an angle that forms a square corner and measures 90 degrees(#13)
acute angle
- an angle that has a measure less than 90 degrees(#14)
straight angle
- an angle that measures 180 degrees(#15)
obtuse angle
- an angle that measures between 90 and 180 degrees(#16)
polygon
- a simple closed figure in a plane formed by three or more line segments(#17)
regular polygon
- a polygon with equal sides and equal angles(#18)
triangle by angle: 1) acute; 2) right; 3) obtuse
- a polygon with 3 sides and 3 vertices: 1) has 3 angles < 90 degrees; 2) has 1 angle = 90 degrees; 3) has 1 angle > 90 degrees(#19)
triangle by side: 1) equilateral; 2) isosceles; 3) scalene
- a polygon with 3 sides and 3 vertices: 1) all sides are equal; 2) 2 sides are equal; 3) no sides are equal
quadrilateral
- a polygon with four sides and four vertices
parallelogram
- a quadrilateral with both pairs of opposite sides equal in length and parallel
types of parallelograms: rectangle, rhombus, square
1) parallelogram with 4 right angles; 2) parallelogram with 4 equal sides; 3) parallelogram with 4 equal sides and 4 right angles.
quadrilaterals that are NOT parallelograms: trapezoid, kite, other
1) quadrilateral with 1 pair only of parallel sides; 2) quadrilateral with 2 pairs of equal sides which are next to each other; 3) quadrilaterals that fit none of the other patterns
Other polygons: pentagon, hexagon, heptagon, octagon, nonagon, decagon
- polygon with 5 sides, 6 sides, 7 sides, 8 sides, 9 sides, 10 sides
Sums of angles: triangles and quadrilaterals
triangle - 180 degrees; quadrilateral - 360 degrees
congruent
- describes figures that have exactly the same size and same shape
line of symmetry
- divides a figure into congruent parts
similar
- describes figures that are the same shape but may be a different size
transformation
- a change of position
slide (translation)
- the figure moves up/down, left/right, diagonally
flip (reflection)
- the figure produces a mirror image (congruent)
turn (rotation)
- figure moves around a fixed point