Search
Create
Log in
Sign up
Log in
Sign up
Chapter 16 Envisions Vocabulary
STUDY
Flashcards
Learn
Write
Spell
Test
PLAY
Match
Gravity
Terms in this set (38)
point
is an exact location in space
line
is a straight path of points that goes on and on in two directions
plane
is an endless flat surface
parallel lines
two lines that never intersect
intersecting lines
lines that pass through the same point
perpendicular lines
lines that form square corners (90 degree angles)
line segment
a part of a line with two endpoints
ray
is a part of a line that has one endpoint and continues on forever in one direction
angle
is a figured formed by two rays that have the same endpoints.
right angle
is an angle with a square 90 degree corner
acute angle
is an angle that is open less than a right angle ( less than 90 degrees)
obtuse angle
is an angle that is open more than a right angle (more than 90 degrees)
straight angle
is an angle that forms a straight line
unit angle
is an angle that cuts off 1/360 of a circle and measures 1 degree.
degrees
angles are measured in units called
angle measure
the degrees of a certain angle
protractor
a tool that is used to measure and draw angles
polygon
is a closed flat shape or plane made up of line segments
sides
each is a line segment
vertex
the point where two sides meet
triangle
a polygon with three sides
quadrilateral
a polygon with four sides
pentagon
a polygon with five sides
hexagon
a polygon with six sides
octagon
a polygon with eight sides
equilateral triangle
a triangle with 3 equal sides
isosceles triangle
a triangle with 2 equal sides
scalene triangle
a triangle with 0 equal sides
right triangle
a triangle with one right angle.
acute triangle
is a triangle with three acute angles. All of its angles measure less than a right angle.
obtuse triangle
is a triangle with one obtuse angle. One angle has a measure greater than a right angle.
rhombus
is a quadrilateral that has opposite sides that are parallel and all of its sides are the same length.
trapezoid
is a quadrilateral with only one pair of parallel sides.
parallelogram
has two pairs of parallel lines.
rectangle
has 4 right angles. It is also a parallelogram.
square
has 4 right angles and all sides are the same length. It is a parallelogram, rectangle, and a rhombus.
symmetric
if it can be folded on a line to form two equal halves that fit on top of each other.
line of symmetry
the fold line is called
;