10. WHEN TWO TRIANGLES ARE THE SAME SIZE AND SHAPE, THEY ARE CONGRUENT. IF WE HAVE INFORMATION THAT PRODUCES A UNIQUE TRIANGLE, WE CAN CHECK TO SEE IF IT IS CONGRUENT TO ANOTHER. CHECK THE TWO WORKSHEETS FROM THE LAST TWO LESSONS.

11. THE MINIMUM AMOUNT OF INFORMATION NEEDED IS EITHER: THREE EDGES ONE EDGE AND TWO ANGLES TWO EDGES AND ONE ANGLE (IN SPECIAL CASES)

12. WITH THIS INFORMATION WE CAN CHECK WHETHER TWO TRIANGLES ARE CONGRUENT: THREE EDGES 5cm4cm 2cm 5cm4cm 2cm (SSS) ONE EDGE AND TWO ANGLES 4cm 80 o 60 o 80 o 60 o (AAcorS)

13. ONE EDGE AND TWO ANGLES 4cm 80 o 60 o 80 o 60 o (AAcorS) THIS MEANS “TWO ANGLES AND A CORRESPONDING SIDE”. THE ANGLES MUST BE IN THE SAME PLACE IN RELATION TO THE SIDE. NOTE: THESE ARE NOT CONGRUENT… 4cm 80 o 60 o 80 o 60 o

14. WITH THIS INFORMATION WE CAN CHECK WHETHER TWO TRIANGLES ARE CONGRUENT: TWO EDGES WITH AN ANGLE BETWEEN THEM 5cm4cm 40 o 5cm4cm 40 o (SAS) THE HYPOTENUSE AND ANY OTHER CORRESPONDING SIDE 5cm 3cm (RHS)

15. RHS MEANS “RIGHT HYPOTENUSE SIDE” BUT REALLY THIS RULE WORKS FOR ANY TWO SIDES ON A RIGHT-ANGLED TRIANGLE. THE HYPOTENUSE AND ANY OTHER SIDE 5cm 3cm (RHS) NOTE: HYPOTENUSE IS THE LONGEST EDGE. NOTE: THESE ARE ALSO CONGRUENT BY SAS. 4cm 3cm