| A | B |
|---|
| line | extends indefinitely in two directions |
| ray | extends indefinitely in one direction |
| segment | part of line with two endpoints |
| angle | formed by two rays with common endpoint |
| vertex | common endpoint |
| sides | rays of an angle |
| protractor | tool used to measure angles |
| acute angle | between 0 and 90 degrees |
| right angle | exactly 90 degrees |
| obtuse angle | between 90 and 180 degrees |
| congruent angles | angles with same measure |
| complementary angles | angles whose measures sum to 90 |
| supplementary angles | two angles whose sum is 180 |
| acute triangle | triangle with 3 acute angles |
| right triangle | triangle with one right angle |
| obtuse triangle | triangle with one obtuse angle |
| scalene triangle | triangle with no congruent sides |
| isosceles triangle | triangle with 2 congruent sides |
| equilateral triangle | triangle with 3 congruent sides |
| Mr. | Smith |
| P=a+b+c | Perimeter of triangle |
| P=4s | Perimeter of square |
| P=2l+2w | Perimeter of Rectangle |
| C=2*pi*r | Circumference of Circle |
| A=l*w | Area of Rectangle |
| A=s*s | Area of Square |
| A=b*h | Area of Parallelogram |
| A=1/2 b*h | Area of Triangle |
| A=pi*r*r | Area of Circle |
| 180 | sum of 3 angles in a triangle |
