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mixed number

A mixed number is the sum of a whole number and a fraction.

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intersect

when two lines cross

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point of intersection

the place where the lines cross

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parallel lines

if two lines in the same plane do not intersect

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perpendicular

if two lines make square corners

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right angles

angles made by perpendicular lines

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straight angle

two right angles

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acute angle

an angle smaller than a right angle

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obtuse angle

an angle smaller than a right angle

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polygon

the number of sides is always equal to the number of vertices

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side

each segment of a polygon

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vertex {plural: vertices}

endpoint of a side

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concave polygon

if a polygon has a indentation

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convex polygon

any polygon that does not have an indentation

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parallelogram

quadrilateral that has two pairs of parallel sides

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trapezoid

is a quadrilateral that has exactly two parallel sides

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rhombus

equilateral parallelogram

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square

rhombus with four right angles

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perimeter

measure around or distance around

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radius

distance from the center of the circle

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diameter

twice the length of the radius

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circumference

perimeter of a circle

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circumference of a circle

pi D=pi(2r)=2(pi)r

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infinte numbers

(1, 3, 5, 7 ....)

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finite numbers

(1, 3, 4, 6 )

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