Which of the following represents the length
of the missing side to the nearest tenth?

Answer:
8.9
Step-by-step explanation:
Use Pythagorean Theorem (a²+b²=c²)
a²+8²=12²
a²+64=144
Subtract 64 to both sides
a²=80
Square root both sides
a=√80
√80≈8.9