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right angle

an angle that measures 90 degrees

vertical angle

the opposite angles where two lines meet

complementary angles

two angles whose sum is a right angle, angles that add up to 90 degrees

supplementary angles

two angles whose sum is 180 degrees

congruent angles

angles with the same measure

intersecting lines

lines that meet at one point, Lines that cross at exactly one point

parallel lines

lines in the same plane that never intersect

transversal

a line that intersects two or more lines.

angle

consists of two rays that begin at the same point

line

a straight path of points that extends without an end in opposite directions

line segment

a part of a line between two endpoints

vertex

the point at the corner of an angle, plane figure or solid figure

acute angle

an angle that measures between 0 and 90 degrees

obtuse angle

an angle that measures between 90 and 180 degrees

straight angle

an angle that measures 180 degrees only (remember 180 degrees only)

adjacent angle

side by side angles that share a common vertex and a ray.