acute angle

an angle less than 90 degrees but more than 0 degrees

obtuse angle

an angle between 90 and 180 degrees

perpendicular lines

lines that intersect to form right angles

point

a location in space. It takes only one letter to name me.

line segment

a line that connect 2 points

part of a line with two endpoints

part of a line with two endpoints

parallel lines

lines that will never meet;

lines that never intersect

lines that never intersect

vertex

The common endpoint of an angle, the point where two rays, lines or line segments meet to form an angle

intersecting

lines, rays or segments that cross

right angle

an angle that measures 90 degrees

straight angle

an angle that measures 180 degrees

isosceles triangle

A triangle with two congruent sides

scalene triangle

A triangle with no congruent sides; no sides are equal

equilateral triangle

a triangle with 3 congruent sides

congruent

same shape and same size

right triangle

a triangle with one right angle

ray

a straight path that extends infinitely from an endpoint

line

a straight path that extends infinitely in oppposite directions

quadrangle

a polygon with 4 sides and 4 angles