| A | B |
|---|
| isosceles | triangles with at least 2 congruent sides |
| equilateral | triangles with 3 congruent sides |
| scalene | triangles with no congruent sides |
| base angles | the angles of an isosceles triangles that are opposite the congruent sides |
| equiangular | triangles with 3 congruent angles |
| 180 degrees | the sum of the 3 interior angles |
| exterior angle | equal to the two remote interior angles |
| right triangle | a triangle with a 90 degree angle |
| acute | a triangle where all angles are less than 90 degrees |
| obtuse | one angle in a triangle is more than 90 but less than 180 degrees |
| right triangle corollary | the 2 acute angles of a right triangle are equal to 90 degrees |
