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What is 1 + 3?
A straight path that goes on forever in opposite directions.
A label that is a line with arrows on both ends.
A part of a line that has one endpoint and extends without end in one direction.
A label that is a line with an arrow on one end
A figure formed by two rays or line segments with two endpoints.
A label that is similar to a "less than symbol" only flat on the bottom.
The same distance apart at every point.
Lines, line segments, or rays are this if they form right angles.
Lines that are not parallel or perpendicular.
A semicircular instrument for measuring and constructing angles.
A unit of measuring angles. Also a unit for measuring temperature.
An angle that measure 90 degrees.
Lines that cross at the same point.
Two angles whose sum of their measures is 90 degrees.
Two angles whose sum of their meaures is 180 degrees.
Angle greater than 0 degrees and less than 90 degrees.
A 90 degree angle.
Angle greater than 90 degrees and less than 180 degrees.
A 180 degree angle.
Angle greater than 180 degrees and less than 360 degrees.
A shape that measures 360 degrees.
A two-dimensional figure with four sides.
figures that are the same shape and size.
A closed plane figure with sides made of straight line segments.
A pair of opposite angles formed by intersecting lines.
These angles are formed by two intersecting lines and have the same measure.
The sum of the interior angles of a quadrilateral.
The sum of the interior angles of a triangle.