Answer:
All of the above
Step-by-step explanation:
dy/dt = y/3 (18 − y)
0 = y/3 (18 − y)
y = 0 or 18
d²y/dt² = y/3 (-dy/dt) + (1/3 dy/dt) (18 − y)
d²y/dt² = dy/dt (-y/3 + 6 − y/3)
d²y/dt² = dy/dt (6 − 2y/3)
d²y/dt² = y/3 (18 − y) (6 − 2y/3)
0 = y/3 (18 − y) (6 − 2y/3)
y = 0, 9, 18
y" = 0 at y = 9 and changes signs from + to -, so y' is a maximum at y = 9.
y' and y" = 0 at y = 0 and y = 18, so those are both asymptotes / limiting values.
Answer:
$153
Step-by-step explanation:
To find the total cost, we have to calculate the area of one bead, then all of them:
Area of one bead = pi x r^2 = 3.14 x 0.5^2 = 3.14 x 0.25 = 0.765cm^2
Area of 20 beads = 0.765 x 20 = 15.3cm^2
Now, we are able to calculate the ultimate cost of coating:
If the cost is $10 per cm^2, then we have to find how much it costs to coat 15.3 cm^2.
15.3 x 10 = $153.
Hope this helps
Answer:
x = 3, y = - 2
Step-by-step explanation:
By substitution method,
4x + y = 10 -------> equation 1.
7x + 2y = 17 -------> equation 2.
From equation 1,
y = 10 - 4x ------> equation 3.
Substitute equation 3 in 2,
7x + 2 ( 10 - 4x ) = 17
7x + 20 - 8x = 17
7x - 8x = 17 - 20
- x = - 3
x = 3
Substitute x = 3 in equation 1,
4 ( 3 ) + y = 10
12 + y = 10
y = 10 - 12
y = - 2
Hence,
x = 3
y = - 2
When substituting, you want to take the y value from one equation and plug it into the y variable in the other equation to find the x value. When you find the c value, you plug the number into one of the equations to get your y value.
3(2x-6)-7x+4
3*2x=6x. 3*-6=-18
-7x+6x=-1x. -18+4=-14
-1x/-1=x. -14/-1=14
X=14