Answer:
x = 
Step-by-step explanation:
Use Pythagorean theorem,
Hypotenuse² = base² + altitude²
x² = (√8)² + 4²
= 8 + 16
= 20
x = √20 = 
x = 
P=0.042
So the answer should be b.
We have the next inequation
8-4x<56
-4x<56-8
-4x<48
-x<48/4
-x<12
x>-12
Solution: x>-12 or (-12,+∞)