Answer:
b)0, yes
Step-by-step explanation:
Given:
Vectors (4,8) . (6,-3)
Finding inner product of vectors:
= 4x6 + 8x-3
=24-24
=0
Now to check the angle between them using formula a.b=|a|.|b|cosθ
|a|= 
=8.9
|b|=
=6.7
Putting values of a.b=0 and |a|=8.9, |b|=6.7 in a.b=|a|.|b|cosθ we get,
0= 8.9(6.7)cosθ
cosθ =0
θ=90 degrees
Hence the two vectors are perpendicular !
Can you put a picture of the graph?
Answer:
H(d) = 0.3d + 12
Step-by-step explanation:
It started at 12 inches.
Then it grew 0.3 inches per day.
Let d = number of days.
The growth is 0.3 d.
Add the growth to the original length, to get 0.3d + 12.
Answer: H(d) = 0.3d + 12
Answer: the cost of an adult ticket is $21.5
the cost of a child ticket is $15.5
Step-by-step explanation:
Let x represent the cost of an adult ticket.
Let y represent the cost of a child ticket.
At an amusement park, the cost of 3 adult tickets and 4 children's tickets is $126.50. It means that
3x + 4y = 126.5- - - - - - - - - - - -1
Another customer paid $120.50 for 2 adult tickets and 5 children's tickets. It means that
2x + 5y = 120.5- - - - - - - - - - - -2
Multiplying equation 1 by 2 and equation 2 by 3, it becomes
6x + 8y = 253
6x + 15y = 361.5
Subtracting, it becomes
- 7y = - 108.5
y = - 108.5/ - 7
y = 15.5
Substituting y = 15.5 into equation 1, it becomes
3x + 4 × 15.5 = 126.5
3x + 62 = 126.5
3x = 126.5 - 62
3x = 64.5
x = 64.5/3
x = 21.5
Interest rate of the account is 5.5%, if Nadia deposited $3000 into an account that earns annual simple interest after 6 years, she had earned $990 in interest.
Step-by-step explanation:
The given is,
Nadia deposited $3000
After 6 years, she had earned $990 in interest
Simple interest
Step:1
Formula to calculate the future amount with simple interest is,
...........................(1)
Where, F - Future amount
P - Initial investment
r - Rate of interest ( simple interest )
t - No. of years
Step:2
From the given,
I = $990
P = $3000
F = Initial investment + Interest amount
F = P + I = 3000 + 990 = $3990
t = 6 years
Equation (1) becomes,
3990 = 3000 ( 1 + (r)(6) )

1.33 = 1 + (r)(6)
1.33 - 1 = (r)(6)
0.33 = (r)(6)

r = 0.055 × 100
r = 5.5%
Result:
Interest rate of the account is 5.5%, if Nadia deposited $3000 into an account that earns annual simple interest after 6 years, she had earned $990 in interest.