Question | Answer |
Has a measure of 90°. | right angle |
Lines in a plane that never meet. | parallel lines |
A shape with this has two halves that are mirror images of each other. | reflection symmetry |
Two lines that intersect to form right angles. | perpendicular lines |
A polygon with at least two sides with different lengths or two angles with different measures. | irregular polygon |
The angle inside a polygon formed by two adjacent sides of the polygon. | interior angle |
An angle with a vertex at the center of a circle. | central angle |
A line segment connecting two nonadjacent vertices of a polygon. | diagonal |
A polygon in which all the sides are the same length. | regular polygon |
An angle outside the polygon formed by extending a side of the polygon. | exterior angle |
A line that intersects two or more lines. | transversal |
An angle that measures 180°. | straight angle |
A line such that if a shape is folded over it, the two halves of the shape match perfectly. | line of symmetry |
An angle whose measure is less than 90°. | acute angle |
A closed shape formed by line segments. | polygon |
An angle whose measure is greater than 90° and less than 180°. | obtuse angle |
A parallelogram with all right angles, including squares which are a special type. | rectangle |
A quadrilateral with opposite sides parallel. Both pairs of opposite angles are also equal. | parallelogram |
A triangle with no side lengths equal. | scalene triangle |
The point where two sides of a polygon or two rays meet. | vertex |
Covering a flat surface with shapes that fit together without any gaps or overlaps. | tiling |
A shape can be turned less than 360° about its center to a position where it looks exactly as it did before it was turned. | rotation symmetry |
Two points of a line and all the points between these two points. | line segment |
A triangle with two sides the same length. | isosceles triangle |
A triangle with all sides and all angles equal to each other. | equilateral triangle |
The sum of all the measures of the interior angles of a polygon. | angle sum |