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:
what the heck
was that also i'm country
Step-by-step explanation:
Answer:
70 cm^2
Step-by-step explanation:
The area of square is 5×10=50 plus the square of triangle, high of triangle is 18-10=8 and base of triangle is 5 because it common base with square, so the square of triangle is 1/2(8)(5)=20
The total area is 50+20=70 cm^2
Answer:
1 1/4
Step-by-step explanation:
3 1/8 - 1 7/8
I like to line them up vertically
3 1/8
- 1 7/8
---------------
We need to borrow from the 3
Take 1 from the 3 and make it 8/8
2 (1/8+8/8)
- 1 (7/8)
---------------------
2 (9/8)
- 1 (7/8)
---------------------
1 2/8
Simplify the fraction by dividing by 2 on the top and bottom
1 1/4