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.
0.4 is 4/10 in decimal form.
Answer:
P' (- 7, - 5 )
Step-by-step explanation:
A translation of 3 units to the left means subtractin 3 from the x- coordinate with no change to the y- coordinate, thus
P(- 3, 5 ) → (- 3 - 4, 5 ) → (- 7, 5 )
Under a reflection in the x- axis
a point (x, y ) → (x, - y ), thus
(- 7, 5 ) → P'(- 7, - 5 )
