Respuesta :
a straight edge, or a right angle, whatever you call it.
If you have sides a, b and c, and c = √(a²+b²), you know that a and b are perpendicular.
If you have sides a, b and c, and c = √(a²+b²), you know that a and b are perpendicular.
Answer:
The answer should be congruent sides.
Step-by-step explanation: