-2 and -2 Two negatives added equal a positive.............. . . .. . . . . . .
interior angle of a regular 18-gon.
It is easier to calculate the exterior angle of a regular polygon of n-sides (n-gon) by the relation
exterior angle = 360/n
For a 18-gon, n=18, so exterior angle = 360/18=20 °
The value of each interior angle is therefore the supplement, or
Interior angle = 180-20=160 degrees.
Naming of a 9-gon
A polygon with 9 vertices is called a nonagon (in English) or enneagon (French ennéagone, but the English version is sometimes used)
You had a good start with the correct answer.
Exterior angle of a 15-gon
The exterior angle of a 15-gon can be calculated using the relation given in the first paragraph, namely
Exterior angle = 360/15=24 degrees
Answer:
Due to the higher z-score, he did better on the SAT.
Step-by-step explanation:
When the distribution is normal, we use the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
Determine which test the student did better on.
He did better on whichever test he had the higher z-score.
SAT:
Scored 1070, so 
SAT scores have a mean of 950 and a standard deviation of 155. This means that
.



ACT:
Scored 25, so 
ACT scores have a mean of 22 and a standard deviation of 4. This means that 



Due to the higher z-score, he did better on the SAT.
2^4-8x2/4 (PEMDAS) Parenthesis, Exponents, Multiplication, Division, Addition, Subtraction
first you want to do exponents.. so 2x2x2x2 = 16
then you want to do multiplication so.. -8x2 = -16
now you have.. 16-16/4 .. then you want to do division so divide -16 by 4 and get -4
then you're left with 16-4 which is 12
THE ANSWER IS 12