Usage of the pythagorean theorem and the law of cosine?

Question

hi just tell me if i am right....

we use the pythagorean theorem if alpha or beta or gama is 90 degrees

we use the law of cosine if we dont know any angle

we can also use the law of cosine if one angle is 90 degrees but its just faster with the pythagorean theorem

i am little confused right now :D

Answer 1

i don't know. sorry but I can't remember anything from my trig teacher.

Answer 2

correct, alexa

Answer 3

your very right!! good job