Answer:
see below
Step-by-step explanation:
I will be using pythagorean triples for some, but you can use sqrt(a^2+b^2)=c^2
1. 12 13 5 x=5
2. 3 4 5 x=5
3. sqrt(14.7^2-11.9^2)=sqrt(74.48) or around 9 (root is irrational)
4. sqrt(15.4^2-6.3^2)=sqrt(197.47) or around 14 (same thing)
5. sqrt(15^2-11^2)=2*sqrt(26) or around 10
6. sqrt(4^2-sqrt(6)^2)=sqrt(16-6)=sqrt(10) or around 3
7. sqrt(12^2+9^2)= 15, so it is a right triangle
8. 9, 12, 15 divide by 3- 3, 4, 5 pythagorean triple - is a right triangle
9. 9, 12, 15-17>15, obtuse
10. sqrt(20.1^2+18^2)=20.4 - 20.1<20.4, acute
11. sqrt(4.8^2+28.6^2)=29, 29=29, right
