| A | B |
|---|
| triangle | a figure formed by three segments joining three noncollinear points |
| isosceles triangle | triangle with at least 2 congruent sides |
| equilateral triangle | triangle with three congruent sides |
| scalene triangle | triangle with no congruent sides |
| equiangular triangle | triangle with three congruent angles |
| acute triangle | triangle with 3 acute sides |
| right triangle | triangle with on right angle |
| obtuse triangle | triangle with one obtuse angle |
| obtuse angle | angle measure larger than 90 degrees |
| acute angle | angle measure that is less than 90 degrees |
| right angle | angle measure of 90 degrees |
| corollary | a statement that can be proved easily using the theorem |
| interior angles | three original angles in a triangle |
| exterior angles | the angles that are adjacent to the interior angles |
| legs | the congruent sides of an isosceles triangle |
| base | the other side in an isosceles triangle (not the legs) |
| base angles | the two angles at the base of the triangle |
