Answer: Choice D)
The angle between the two vectors is approximately 71.6 degrees
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Work Shown:
Each time I write the word "dot" I mean "dot product".
|u| = length of vector u
|u| = sqrt(u dot u)
|u| = sqrt(<8,4> dot <8,4>)
|u| = sqrt(8*8 + 4*4)
|u| = sqrt(64 + 16)
|u| = sqrt(80)
|u| = sqrt(16*5)
|u| = sqrt(16)*sqrt(5)
|u| = 4*sqrt(5)
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|v| = length of vector v
|v| = sqrt(v dot v)
|v| = sqrt(<9,-9> dot <9,-9>)
|v| = sqrt(9*9 + (-9)*(-9))
|v| = sqrt(81+81)
|v| = sqrt(2*81)
|v| = sqrt(2)*sqrt(81)
|v| = sqrt(2)*9
|v| = 9*sqrt(2)
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u dot v = <8,4> dot <9,-9>
u dot v = 8*9 + 4*(-9)
u dot v = 72-36
u dot v = 36
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cos(theta) = (u dot v)/(|u|*|v|)
cos(theta) = (36)/(4*sqrt(5)*9*sqrt(2))
cos(theta) = (36)/(36*sqrt(10))
cos(theta) = 1/(sqrt(10))
cos(theta) = sqrt(10)/10
theta = arccos(sqrt(10)/10)
theta = 71.56505
which rounds to 71.6 when rounding to one decimal place (nearest tenth)
That's why the approximate answer is roughly 71.6 degrees
Distance formula = sqrt[(4^2 + 3^2) - 2(3×4)cos(73-12)]
sqrt[(25) - 24cos(61)]
sqrt(25 - 11.64)
sqrt(13.36)
final answer = 3.66
Hope this helps!
Answer:
3.54% probability of observing at most two defective homes out of a random sample of 20
Step-by-step explanation:
For each house that this developer constructs, there are only two possible outcomes. Either there are some major defect that will require substantial repairs, or there is not. The probability of a house having some major defect that will require substantial repairs is independent of other houses. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

In which
is the number of different combinations of x objects from a set of n elements, given by the following formula.

And p is the probability of X happening.
30% of the houses this developer constructs have some major defect that will require substantial repairs.
This means that 
If the allegation is correct, what is the probability of observing at most two defective homes out of a random sample of 20
This is
when n = 20. So






3.54% probability of observing at most two defective homes out of a random sample of 20
Answer:
Explanation and problem 1 solved below.
Step-by-step explanation:
The quadrants are numbered this way:
Quadrant 1: upper right
Quadrant 2: upper left
Quadrant 3: lower left
Quadrant 4: lower right
Signs of coordinates in the quadrants:
x-coordinate is positive in Q1 and Q4
x-coordinate is negative in Q2 and Q3
y-coordinate is positive in Q1 and Q2
y-coordinate is negative in Q3 and Q4
1. (-1, 5)
x is negative, so it is Q2 or Q3
y is positive, so it is Q1 or Q2
The quadrant in common is Quadrant 2
Answer: quadrant 2
Answer:
D
Step-by-step explanation:
Given the 2 equations
y = x - 5 → (1)
y = x² - 5x + 3 → (2)
Substitute y = x² - 5x + 3 into (1)
x² - 5x + 3 = x - 5 ← subtract x - 5 from both sides
x² - 6x + 8 = 0 ← in standard form
(x - 2)(x - 4) = 0 ← in factored form
Equate each factor to zero and solve for x
x - 2 = 0 ⇒ x = 2
x - 4 = 0 ⇒ x = 4
Substitute each of these values into (1) for corresponding values of y
x = 2 → y = 2 - 5 = - 3 ⇒ (2, - 3 )
x = 4 → y = 4 - 5 = - 1 ⇒ (4, - 1 )