Answer:
7a-7
Step-by-step explanation:
2a+2−3a−5+a−4+7a.
Combine like terms
2a-3a+a+7a+2-5-4
7a-7
Q) Without a calculator, we must estimate the value of the following expression:
![3-\sqrt[]{38}.](https://tex.z-dn.net/?f=3-%5Csqrt%5B%5D%7B38%7D.)
A) I estimate 3 - √38 to be approximately -3.2.
First, we estimate the value of √38. √38 is between √36 and √49, but close to √36 (since 38 is closer to 4 than it is to 9). Since √36 is 6, √38 is probably something like 6.1 or 6.2. Filling 6.2 in the expression and simplifying, we have this:

So, I expect the number 3 - √38 to be close to -3.2.
Using a calculator we find that: 3 - √38 ≅ -3.16, which it is approximately the result that we found.
Answer
Without a calculator we find that 3 - √38 ≅ -3.2.
<h2>
Answer with explanation:</h2>
Let
be the average starting salary ( in dollars).
As per given , we have

Since
is left-tailed , so our test is a left-tailed test.
WE assume that the starting salary follows normal distribution .
Since population standard deviation is unknown and sample size is small so we use t-test.
Test statistic :
, where n= sample size ,
= sample mean , s = sample standard deviation.
Here , n= 15 ,
, s= 225
Then, 
Degree of freedom = n-1=14
The critical t-value for significance level α = 0.01 and degree of freedom 14 is 2.62.
Decision : Since the absolute calculated t-value (2.07) is less than the critical t-value., so we cannot reject the null hypothesis.
Conclusion : We do not have sufficient evidence at 1 % level of significance to support the claim that the average starting salary of the graduates is significantly less that $42,000.
Answer:
x= 2x+3
Step-by-step explanation:
delta= postif
x1= -b - racine de Delta sur A AU CARRE
x2= -b + racine de delta A AU CARRE
Answer:
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