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a location in space


points that lie on the same line

line segment

a part of a line consisting of two endpoints and all the points between


a part of a line that begins at one endpoint and extends without end in the other directions


points or lines that do not lie in the same plane


the figure formed by two rays that have a common endpoint


a set of points that extends infinitely in two directions


a flat surface that extends endlessly in all directions


points that do not lie on the same line


points or lines that lie in the same plane

acute angle

an angle that measures less than 90 degrees

right angle

an angle that measures exactly 90 degrees

obtuse angle

an angle that measures greater than 90 degrees

straight angle

an angle that measures 180 degrees


two lines that intersect at a right angle are called

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