Question

PLEASE PLEASE PLEASE HELP!!

I'll seriously appreciate it, and thank you so so so much in advance!!
DON'T ANSWER IF YOU'RE UNSURE!!! I need actual help, please don't just take my points. (: Thank you!

Answer 1

If a^2+b^2=c^2 then it's a right angle
If a^2+b^2>c^2 then it's acute
If a^2+b^2< c^2 then it's obtuse. 3.1^2+3^2. 5^2
1+9. < 25
#3 is obtuse
4. 28^2+45^2. 53^2
2809. 2809
#4 is a right triangle
5. 9^2+11^2. 13^2
81+ 121 =202.> 169
#5 is acute