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:
simplee really...
Step-by-step explanation:
7. 3/5 = 4.5/x
3x= 5(4.5)
x = 15/2
8. 6/4 = 9/x
6x= 45
x= 15/2
8. since triangle ABC and ADE are identical,
angle E is also 30 degrees
so angle D = 180-(30+70)=80 degrees
9. 9/3 = x/5
3x = 45
x = 45/3 = 15
Answer:
answer
Step-by-step explanation:
