Answer: x+4
Step-by-step explanation:
(x-9)(x+4)= x^2-5x-36
Answer:
(a+b)(a-b)
Step-by-step explanation:
because (a+b)(a-b):
If you use FOIL it will work backwards
First off, do a prime factoring of the constant and leading coefficient, namely 9 and 8 respectively.
so a prime factoring of 8 is 2*2*2, and a prime factoring of 9 is 3*3.
so, those are the factors... now, how do we produce products that gives us the middle coefficient +18?
well, let's see hmmmm 2 * 3 * 3 and 2 * 3....so that's 18 + 6, that's 24.. .so... no good is not 18, let's try again.
2*2*3 and 2 * 3, so that's 12 + 6, now, that's +18
so we'll use those, 2*2*3 and 2*3, or 4 * 3 an 2 * 3, (4x + 3)(2x + 3) = 0.
Answer:
x= -8 x=2
Step-by-step explanation:
x^2 +6x-6= 10
Subtract 10 from each side
x^2 +6x-6-10= 10-10
x^2 +6x-16 = 0
What 2 number multiply to -16 and add to 6
8 * -2 = -16
8 -2 = 6
(x+8) (x-2)=0
Using the zero product property
x+8=0 x-2=0
x= -8 x=2
Answer:
a) The 95% confidence interval to estimate the average fee for the population is between $11.65 and $12.79
b) $0.57
Step-by-step explanation:
We have that to find our 
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of 
.
So it is z with a pvalue of 
, so 
Now, find the margin of error M as such
In which 
is the standard deviation of the population and n is the size of the sample.
So the answer for b) is $0.57.
The lower end of the interval is the sample mean subtracted by M. So it is 12.22 - 0.57 = $11.65
The upper end of the interval is the sample mean added to M. So it is 12.22 + 0.57 = $12.79
The 95% confidence interval to estimate the average fee for the population is between $11.65 and $12.79
