Answer:
1 . √98 = √49 · 2 = 7√2
2. 28² + 45² = 2809
√2809 = 53 = x
3. 18² - 12² = 180
√180 = √36 ·5 = 6√5
4. 5² + 7² ? 9²
74 ? 81
Since 74 is less than 81, it is obtuse
5. 3² + 5² = √34²
34 = 34, so it is right
6. ? = SR
7. 5/x = x/3
x² = 15
x = √15
8. Using 45 45 90 special triangle properties,
x = 10√2