Step-by-step explanation:
For the quadratic equation to have 1 repeated real solution, the discriminant b² - 4ac must be zero.
=> (-z)² - 4(z - 5)(5) = 0
=> z² - 20(z - 5) = 0
=> z² - 20z + 100 = 0
=> (z - 10)² = 0
Therefore z = 10.
12 + 6x + 6x + 6y = 12 + 12x + 6y
Answer:
a) n = 1037.
b) n = 1026.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of 
The margin of error is:

99% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
(a) Assume that nothing is known about the percentage to be estimated.
We need to find n when M = 0.04.
We dont know the percentage to be estimated, so we use
, which is when we are going to need the largest sample size.






Rounding up
n = 1037.
(b) Assume prior studies have shown that about 55% of full-time students earn bachelor's degrees in four years or less.

So






Rounding up
n = 1026.
If you paid attention in math, you would know this lol jk.
But you would rewrite it as 5+4
The correct answer would be A