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What is 1 + 3?
names a location
perfectly straight surface and extends forever in both directions
a perfectly flat surface and extends forever in all directions.
part of a line between two points
part of a line that starts at one point and extends forever in one direction.
formed by two rays with a common endpoint called a vertex.
measures 90 degrees
measures less than 90 degrees
greater than 90 degrees yet less than 180 degrees
have measures that add to 90 degrees
have measures that add up to 180 degrees.
have the same shape and size
lines in a plane that never meet
lines that intersect at 90 degrees
line that intersects two or more lines that lie in the same plane
Triangle sum theory
angle measures of a triangle in a plane add to 180 degrees
has 3 acute angles
has 1 right angle
1 obtuse angle
has 3 congruent sides and angles
has at least two congruent sides and angles
has no congruent sides or angles
a closed plane figure formed by three or more segments.
a parallelogram with all sides congruent
polygon with one pair of parallel sides
a parallelogram with four right angles
a four sided polygon
a quadrilateral with two pair of parallel sides
a polygon with congruent sides and angles
a rectangle with four congruent sides
a pair of opposite congruent angles formed by intersecting lines