직각삼각형의 정의(Definition of Right Triangle) https://ggbm.at/vzsfaag8 2019022001
RHA 합동 : 직각삼각형의 빗변의 길이와 한 예각의 크기가 각각 같을 때 합동이다.(If two right-angled triangles have their hypotenuses equal in length, and a pair of acute angles are equal in measurement, then the triangles are congruent.) https://ggbm.at/vttxywgg 2017091003
RHS 합동 두 직각삼각형의 빗변의 길이와 다른 한 변의 길이가 각각 같을 때 합동이다(If two right-angled triangles have their hypotenuses equal in length, and a pair of shorter sides are equal in length, then the triangles are congruent.) https://ggbm.at/suwyqgkf 2017091005