Question | Answer |
rectangle | a parallelogram w/ 4 right angles |
ray | a part of a line that starts at one endpoint and extends forever |
complementary angles | two angles whose measures add to 90 |
center of rotation | the point about which a figure is rotated |
congruent | having the same size and shape |
correspondence | the relationship between 2 or mre objects that are matched |
equilateral triangle | a triangle w/ 3 congruent sides |
image | a figure resulting from a transformation |
isosceles triangle | a triangle w/ at least 2 congruent sides |
line | a straight path that extends w/o end in opposite directions |
line of symmetry | the imaginary "mirror" in line symmetry |
line symmetry | a figure has line symmetry if one half is a mirror-image of the other half |
obtuse angle | an angle whose measure is greater than 90 but less than 180 |
obtuse triangle | a triangle containing one obtuse angle |
parallel lines | lines in a plane that do not intersect |
parallelogram | a quadrilateral w/ 2 pairs of parallel sides |
perpendicular lines | lines that intersect to form right angles |
plane | a flat surface that extends forever |
point | an exact location is space |
polygon | a closed plane figure formed by 3 or more line segments that intersect only at their endpoints (vertices) |
vertical angles | a pair of opposite congruent angles formed by intersecting lines |
rhombus | a parallelogram w/ all sides congruent |
right angle | an angle that measures 90 |
right triangle | a triangle containing a right angle |
rise | the vertical change when the slope of a line is expressed as the ratio rise over run |
rotation | a transformation in which a figure is turned around a point |
rotational symmetry | a figure has rotational symmetry if it can be rotated less than 360 around a central point and coincide w/ the original figure |
run | the horizontal change when the slope of a line is expressed as the ratio rise over run |
scalene triangle | a triangle w/ no congruent sides |
segment | a part of a line between 2 endpoints |
semiregular tessellation | a tessellation formed w/ 2 or more regular polygons in which every vertex is identical |
slope | a measure of the steepness of a line on a graph, the rise divided by the run |
square | a rectangle w/ 4 congruent sides |
supplementary angles | two angles whose measures have a sum of 180 |
tessellation | a repeating pattern of plane figures that completely cover a plane with no gaps or overlaps |
transformation | a change in size or position of a figure |
translation | a movement (slide) of a figure along a straight line |
transversal | a line that intersects two or more lines |
trapezoid | a quadrilateral w/ exactly one pair of parallel lines |
regular tessellation | a tessellation formed by using regular polygons |
regular polygon | a polygon w/ congruent sides and angles |
angle | a figure formed by 2 rays w/ a common endpoint called the vertex |
acute triangle | a triangle w/ angles measuring less than 90 |
acute angle | an angle that measures less than 90 |
reflection | a transformation of a figure that flips the figure across a line |
Triangle Sun Theorem | the theorem that states that the measures of the angles in a triangle add up to 180 |