# Geometry 1st 9 weeks

Term Definition
Line straight path moving in both direction without end
Intersecting lines lines that cross
Parallel lines lines that do not meet
Angle two rays with the same endpoint
Open figure figure whose end do not meet
Closed figure figure whose ends meet
Polygon closed figure made up of line segments
Point any exact location
Line segment part of a line with two end points
Ray a line with one end point and extending forever in the other direction
Plane flat surface that extend forever
Quidrilateral a 4 sided figure
Pentagon a polygon with 5 sides
Hexagon polygon with 6 sides
Octagon figure with 8 sides
Decagon figure with 10 sides
Acute angle angles less that 90 degrees
Right angle a 90 degree angle that makes a corner
Obtuse angle an angle greater than 90 degrees
Straight angle 180 degree angle that makes a straight line
Reflex angle an angle greater than a straight angle
Whole angle 360 degree angle that makes complete circle
triangle a figure with three angles