Since the 3 of them are like terms, we have to ADD all 3 of them.
4x+2x+7x= 13x
Domain: {-5, 7}
Range: {-9, 4, 8}
Answer: x>8
Subtract 8 from both sides -6x< -48 (40 is a negative so -8 will just add to it)
Divide -48 and -6
X< 8 (since they’re both negative it’ll turn into a positive because we divided)
Turn the <
X>8
Answer:

And replacing we got:

And then the estimator for the standard error is given by:

Step-by-step explanation:
For this case we have the following dataset given:
20.05, 20.56, 20.72, and 20.43
We can assume that the distribution for the sample mean is given by:

And the standard error for this case would be:

And we can estimate the deviation with the sample deviation:

And replacing we got:

And then the estimator for the standard error is given by:
