Search
Create
Log in
Sign up
Log in
Sign up
Geometry
STUDY
Flashcards
Learn
Write
Spell
Test
PLAY
Match
Gravity
Two-dimensional figures
Terms in this set (52)
right triangle
A triangle that has a 90 degree angle.
obtuse triangle
A triangle where one angle measures over 90 degrees.
equilateral triangle
A triangle with three congruent sides
isosceles triangle
A triangle with 2 congruent sides
scalene triangle
A triangle with no congruent sides
rhombus
a parallelogram with 4 congruent sides
quadrilateral
4 sided polygon
parallelogram
A quadrilateral with two pairs of parallel sides
trapezoid
A quadrilateral with exactly one pair of parallel sides
congruent
Having the same size and shape
similar shapes
Same shape but not the same size: angles are congruent and the sides are proportional
square
A parallelogram with four congruent sides and four right angles.
rectangle
A parallelogram with four right angles
triangle
A polygon with three sides.
hexagon
a polygon with 6 sides
square
A parallelogram with four congruent sides and four right angles.
pentagon
5 sided polygon
polygon
A closed plane figure made up of line segments
octagon
a polygon with 8 sides
right angle
an angle that measures 90 degrees
acute angle
an angle that measures less than 90 degrees
obtuse angle
An angle that measures more than 90 degrees but less than 180 degrees
straight angle
an angle that measures 180 degrees
reflex angle
An angle greater than 180 degrees (but less than 360)
perpendicular
Intersecting at or forming right angles
intersecting
lines that cross at one point
parallel
two or more lines that run in the same direction and do not touch.
heptagon
7 sided polygon
nonagon
9 sided polygon
decagon
10 sided polygon
dodecagon
12 sided polygon
equivalent
equal
regular polygon
a polygon with all sides and all angles equal
irregular polygon
a polygon with sides that are not all congruent or angles that are not all congruent
2 dimensional
flat shape that has 2 dimensions of length and width
3 dimensional
Having 3 dimensions, height, width, and depth.
symmetry
having the same shape, size, and position on both sides of a dividing line
polyhedron
A three-dimensional figure with faces that are polygons
face
A flat surface of a polyhedron
base
a special face on a polyhedron
vertex
A point where two or more straight lines meet.
apex
the highest vertex on a polyhedron
perimeter
the distance around a figure
area
The number of square units required to cover a surface. The inside of a 2-D shape.
circle
a round shape that has no beginning or end
diameter
A straight line passing from side to side through the center of a circle or sphere.
circumference
the distance around a circle
chord
A segment whose endpoints lie on a circle
radius
a straight line from the center to the circumference of a circle or sphere.
prism
A solid figure that has two congruent, parallel polygons as its bases. Its sides are parallelograms
geometrical net
a flattened three-dimensional shape pattern or template.
pyramid
A solid shape with a polygon as a base and triangular faces that come to a point (vertex or apex)
;