Answer:
b = -32 or +32
Step-by-step explanation:
The discriminant of the equation is ...
d = b² -4ac
d = b² -4(2)(128)
d = b² -1024
In order for there to be one real solution, we must have d=0. So ...
0 = b² -1024
1024 = b²
±√1024 = ±32 = b
The value of b can be -32 or +32 to cause the equation to have one real solution.
