Here's your answer to the first problem
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:
the second option is the correct one
Step-by-step explanation:
The equation of a line in point- slope form is
y - b = m(x - a)
where m is the slope and (a, b) a point on the line
To calculate m use the slope formula
m = ( y₂ - y₁ ) / (x₂ - x₁ )
with (x₁, y₁ ) = (7, 5) and (x₂, y₂ ) = (- 4, - 1)
m =
=
= 
Use either of the 2 points as (a, b)
using (- 4, - 1), then
y- (- 1) =
(x - (- 4)), that is
y + 1 =
(x + 4)
Answer:
Sabemos que:
L es el largo de la avenida.
En la primer etapa se asfalto la mitad, L/2, entonces lo que queda por asfaltar es:
L - L/2 = L/2.
En la segunda etapa se asfalto la quinta parte, L/5, entonces lo que queda por asfaltar es:
L/2 - L/5 = 5*L/10 - 2*L/10 = (3/10)*L
En la tercer etapa se asfalto la cuarta parte del total, L/4, entonces lo que queda por asfaltar es:
(3/10)*L - L/4 = 12*L/40 - 10L/40 = (2/40)*L
Y sabemos que este ultimo pedazo que queda por asfaltar es de 200m:
(2/40)*L = 200m
L = 200m*(40/2) = 4,000m
34,590 because even if 0 engines are made, then 34,590 is still expected as a base price