6.6+4.5= 11.1 miles
Erica's house is 11.1 miles away from her friend's house.
Answer:
Step-by-step explanation:
Given the differential equation
25y′′+40y′+16y=0
Using D operator to find the complementary solution
Since the Differential equation is equal to 0, then it doesn't have a partial solution.
25y′′+40y′+16y=0
25D² + 40D +16 = 0
25D² + 20D + 20D +16 = 0
5D(5D+4)+4(5D+4)= 0
(5D+4)=0 twice
D = -4/5 twice,
So the solution is a real and equal roots
y(t) = (A+B•t) exp(—0.8t)
Where A and B are constant
The initial value are.
y(0)=a, y′(0)=−1
y(0) = a = (A+B(0)) exp(—0.8(0))
a = A
Then, the constant A = a.
Now, y'(t)
y'(t)=B•exp(-0.8t)-0.8(A+B•t)exp(-0.8t
-1 = B - 0.8A
Since A =a
Then, B = 0.8a —1
The solution becomes
y(t) = (a+(0.8a-1)•t) exp(—0.8t)
For t>0
For positive,
a + (0.8a -1)> 0
1.8a > 1
a > 1/1.8
a > 10/18 > 5/9
a > 5/9.
Answer:
a = 5 c =11
Step-by-step explanation:
Answer:
75, 77
Step-by-step explanation:
Let the first odd number = 2x -1
Let the second odd number = 2x + 1
2x - 1 + 2x + 1 + 18 = 170 Combine like terms on the left.
4x + 18 = 170 Subtract 18 from both sides.
4x = 170 - 18 Combine like terms on the right
4x = 152 Divide by 4
4x/4 = 152/4
x = 38
2 * 38 - 1 = 75
2 * 38 + 1 = 77
9514 1404 393
Answer:
(b) 48
Step-by-step explanation:
In this geometry, the altitude (x) is the root of the product of the segments of the hypotenuse.
x = √(36·64) = √36×√64 = 6×8
x = 48
_____
All of the triangles are similar, so the ratios of corresponding sides are the same.
short side/long side = x/64 = 36/x
x^2 = (64)(36) . . . . as above
