| A | B |
|---|
| point | identifies a location on an object in space; named by a letter |
| line | a straight path in a plane with no end; named by any two points on the line |
| line segment | part of a line between two endpoints |
| plane | a flat surface with no end |
| perpendicular | lines that intersect to form four right angles |
| parallel | lines in a plane that never intersect and are the same distance from each other |
| intersecting lines | lines that cross at one point |
| ray | a part of a line that has one endpoint and goes on forever in one direction |
| angle | formed when two rays have the same endpoint |
| right angle | forms a square corner; 90 degrees |
| acute angle | less than (90 degrees) a right angle |
| obtuse angle | more than (90 degrees) a right angle |
| congruent | same size, same shape |
| quadrilateral | a polygon with four sides and four angles |
| trapezoid | one pair of parallel sides |
| parallelogram | two pairs of congruent sides, two pairs of parallel sides |
| rectangle | two pairs of congruent sides, four right angles |
| rhombus | four congruent sides, two pairs of congruent angles |
| square | four congruent sides, four right angles |
| scalene triangle | a trinalge with each side a different length |
| isosceles triangle | a triangle that has two congruent sides |
| equilateral triangle | a triangle that has all congruent sides |
