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perpendicular lines

Two lines that intersect to form right angles

intersecting lines

lines that cross at one point

parallel lines

lines in the same plane that never intersect

vertex

The common endpoint of an angle

congruent

Having the same size,length or angle measure

polygon

a closed 2-dimensional shape formed by three or more straight line segments.

trapezoid

a quadrilateral with exactly 1 pair of parallel sides

parallelogram

A quadrilateral opposite sides are congruent and parallel,no right angles

rectangle

a parallelogram with 4 right angles

rhombus

a parallelogram with 4 congruent sides,no right angles

square

a parallelogram with 4 right angles and 4 congruent sides

isosceles triangle

a triangle with two congruent sides

obtuse triangle

a triangle with 1 angle greater than 90 degrees

equilateral triangle

A triangle with 3 congruent sides and 3 congruent angles

scalene triangle

a triangle with no congruent sides

right triangle

a triangle with one 90 degree angle

acute triangle

A triangle with three angles less than 90 degrees.

quadrilaterals

a polygon with four sides,the general term

pentagon

a five-sided polygon

hexagon

a polygon with 6 sides

octagon

A polygon with 8 sides

regular polygon

a polygon with all sides and all angles equal or congruent

faces

flat/plane polygons that make up the sides of a 3-dimensional solid

vertices

points or corners of a polygon or 3-dimensional solid

edges

a line segment where two faces meet on a 3-dimensional solid

net

a 2-dimensional representation of a 3-dimensional solid

area

The number of square units needed to cover a given polygon

dimensions

The length, width, and height of an object being measured.

surface area

The sum of all the areas of all the faces of a 3-dimensional solid.

volume

The amount of space inside a 3-dimensional solid measured in cubic units.