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acute angle

an angle with measure greater than 0 degrees and less than 90 degrees

acute triangle

a triangle in which all three angle measures are less than 90 degrees


the measure in square units of the interior region of a plane figure or the surface of a three dimensional figure

area of triangle

base times height and divide by two


a special side of a polygon used to compute area

composite figure

a shape made of several simpler figures


a segment that joins two vertices of a polygon and is not one of the sides


inverse of multiplication

equilateral triangle

triangle with all three sides the same length


the perpendicular distance between two bases, or a vertex and a base


a polygon with 6 sides

isosceles triangle

a triangle with at least two sides equal in length

line segment

a part of a line with endpoints

obtuse angle

an angle greater than 90 degrees and less than 180 degrees


a polygon with eight sides


two lines which never intersect and are the same distance apart


a quadrilateral with opposite sides parallel


a polygon with five sides


lines, segments or rays that intersect to form right angles


a two dimensional closed figure with straight line segments connected end to end


a polygon with four sides


a portion of a line that has one endpoint and extends forever in one direction


a quadrilateral with four right angles

regular polygon

a polygon with all sides congruent and all angles having the same measure


a quadrilateral with four congruent sides

right angle

an angle with a measure of 90 degrees

right triangle

a triangle with one right angle in it

scalene triangle

a triangle with no two sides of equal length


a quadrilateral with four congruent sides and four rigth angles

square measure

units used to describe the measure of an area in the form of 1 * 1 unit squares


a problem solving strategy which breaks problems into smaller parts which must be solved in order to solve the original problem


quadrilateral with exactly one pair of parallel sides


a polygon with three sides


the point at which two rays, line segments or lines meet.

vertical angles

angles opposite each other when two lines intersect.

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