The left one
The two triangles are congruent because they apply the rule of S-A-S (side - angle - side)
side AB = side AD
angle BAC = angle DAC
side AC on triangle 1 = side AC on triangle 2
The right one
The two triangles are congruent because they apply the rule of R-H-S (right angle - hypotenuse - side)
angle HGJ = angle JLK
hypotenuse GJ = hypotenuse LJ
side HJ = side JK
