Answer:
c=80
Step-by-step explanation:
Based on my reading the critical damping occurs when the discriminant of the quadratic characteristic equation is 0.
So let's see that characteristic equation:
20r^2+cr+80=0
The discriminant can be found by calculating b^2-4aC of ar^2+br+C=0.
a=20
b=c
C=80
c^2-4(20)(80)
We want this to be 0.
c^2-4(20)(80)=0
Simplify:
c^2-6400=0
Add 6400 on both sides:
c^2=6400
Take square root of both sides:
c=80 or c=-80
Based on further reading damping equations in form
ay′′+by′+Cy=0
should have positive coefficients with b also having the possibility of being zero.
Answer:
65+30x
Step-by-step explanation:
You forgot to give the choices.
But, I would think it's 65+30x=
Answer:
The equation for this is: 
Step-by-step explanation:
We have that the number though is n.
Adds 10:
This means that now we have: 
Multiplies by 3:
This means that now we have: 
Gets 42:
This means that: 
Answer: 4 1/10g^5+5 1/4
Step-by-step explanation:
Given:
t = 1/2 √v
v = speed of object meters per second
t = 3 seconds
3 = 1/2 √v
3 * 2 = √v
6 = √v
6² = √v²
36 meters = v
v = 36 meters per second