Answer:
The difference of squares is (a - b)(a + b) = a² - b². Since a = x and b = 2, the answer is x² - 4.
Answer:
Step-by-step explanation:
(b+8)≤18
Answer:
y2-y1, x2-x1
Step-by-step explanation:
4-(-5)= 4-(-8)
4+5=4+8
9=12
9/12
3/4
the slope of line is 3/4
3x600= 3 x 6 hundreds
= 18 hundreds
<span>= 1,800</span>
Answer:
a) 
b) n = 381
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:

90% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
a. Assume that nothing is known about the percentage of computers with new operating systems. n = ?
When we do not know the proportion, we use
, which is when we are going to need the largest sample size.
The sample size is n when M = 0.01.






b. Assume that a recent survey suggests that 99% of computers use a new operating system. n = ?
Now we have that
. So






Rouding up
n = 381