Post on 17-Mar-2016
description
acute angle
An angle that is smaller than a right angle
Example:
acute triangle
A triangle with three acute angles.
Examples:
equilateral triangle
A triangle with 3 equal, or congruent, sides.
Example:
intersecting lines
Lines that cross each other at exactly one point
Example:
isosceles triangle
A triangle with two equal, or congruent, sides.
Example:
obtuse angle
An angle that is larger than a right angle but smaller than a straight angle
Example:
obtuse triangle
A triangle with one obtuse angle.
Example:
parallel lines
Lines in the same plane that never intersect and are always the same distance apart.
Example:
parallelogram
A quadrilateral whose opposite sides are parallel and equal, or congruent.
perpendicular lines
Two lines that intersect to form four right angles
Example:
quadrilateral
A polygon with four sides
Examples:
rhombus
A parallelogram with four equal, or congruent, sides.
Example:
right angle
An angle that forms a square corner
Example:
right triangle
A triangle with one right angle
Example:
scalene triangle
A triangle with no equal, or congruent, sides.
Example:
square
A parallelogram with 4 equal, or congruent, sides and 4 right angles.
Example:
trapezoid
A quadrilateral with exactly one pair of parallel sides
Examples:
convex – used to describe a polygon with all interior angles measuring less than 180 degrees; all diagonals are inside the polygon
concave - used to describe a polygon with at least one angle measuring more than 180 degrees, one or more line segments that are outside the polygon can always be drawn between two vertices
kite – a quadrilateral with no parallel sides, two pairs of congruent sides, and all vertices are convex
opposite angles –angles that touch only at their vertex and share the same lines as sides
similar – having the same shape but not necessarily the same size
vertex - the point where two or more rays meet The plural is vertices.
straight angle – an angle that has a measure of 180 degrees
congruent figures – figures that have the same size and shape