This is Adele's solution for the equation x^2 + 8x - 9 = 0 Step 1 x^2 + 8x - 9 = 0 Step 2 x^2 + 8x = 9 Step 3 ( x + 4 )^2 = 25 S
tep 4 x + 4 = 25 or x + 4 = - 25 Step 5 x = 21 or x = - 29. Where did Adele make her mistake. Show all of your work. 
2 answers:
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Answer:
The values of so that
have vertical asymptotes are
,
,
,
,
.
Step-by-step explanation:
The function cosecant is the reciprocal of the function sine and vertical asymptotes are located at values of so that function cosecant becomes undefined, that is, when function sine is zero, whose periodicity is
. Then, the vertical asymptotes associated with function cosecant are located in the values of
of the form:
,
In other words, the values of so that
have vertical asymptotes are
,
,
,
,
.
Answer:
b. Mean = 1.6 years, standard deviation - 0.92 years, shape: approximately Normal.
Step-by-step explanation:
Central Limit Theorem
The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean and standard deviation
, the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean
and standard deviation
.
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
Subtraction of normal Variables:
When we subtract normal variables, the mean is the subtraction of the means, while the standard deviation is the square root of the sum of the variances.
A consumer group has determined that the distribution of life spans for gas ranges (stoves) has a mean of 15.0 years and a standard deviation of 4.2 years. Sample of 35:
This means that:
The distribution of life spans for electric ranges has a mean of 13.4 years and a standard deviation of 3.7 years. Sample of 40:
This means that:
Which of the following best describes the sampling distribution of the difference in mean life span of gas ranges and electric ranges?
Shape is approximately normal.
Mean:
Standard deviation:
So the correct answer is given by option b.