Answer: it is rational
Step-by-step explanation:
Solve for x:
x^2 + 4 x + 25 = 0 I ssume that's the notation.
Subtract 25 from both sides:
x^2 + 4 x = -25
Add 4 to both sides:
x^2 + 4 x + 4 = -21
Write the left hand side as a square:
(x + 2)^2 = -21
Take the square root of both sides:
x + 2 = i sqrt(21) or x + 2 = -i sqrt(21)
Subtract 2 from both sides:
x = i sqrt(21) - 2 or x + 2 = -i sqrt(21)
Subtract 2 from both sides:
Answer: x = i sqrt(21) - 2 or x = -i sqrt(21) - 2
Answer:
3: alternate interior 4:alternate exterior 5:alternate exterior 6: alternate interior 7:alternate exterior
Step-by-step explanation:
Let the cost for renting be y and the number of hours be x
then:
y=kx
where:
k is the constant of proportionality
k=y/x
y=$32.5 when x=5 hours
thus;
k=32.5/5
k=6.5
hence the equation is:
y=6.5x
thus the value of y when x=8 hours will be:
y=6.5(8)=$52
Answer:'
<span>A y = $6.5x, y = $52.00</span>
Answer:
Step-by-step explanation:
We want to determine a 95% confidence interval for the population mean.
Number of sample, n = 56
Mean, u = 645 hours
Standard deviation, s = 31 hours
For a confidence level of 95%, the corresponding z value is 1.96.
We will apply the formula
Confidence interval
= mean ± z ×standard deviation/√n
It becomes
645 ± 1.96 × 31/√56
= 645 ± 1.96 × 4.142
= 645 ± 8.12
The lower end of the confidence interval is 645 - 8.12 =636.88
The upper end of the confidence interval is 645 + 8.12 =653.12
Therefore, with 95% confidence interval for the population mean life of fluorescent light bulbs is between 636.88 hours and 653.12 hours
