This is a perfect square trnomial
(a+b)²=a²+2ab+b²
we see that a=5x and b=2
(5x)²+2(5x)(2)+2²=0
factor
(5x+2)²=0
set equal to zero
5x+2=0
5x=-2
x=-2/5
Answer:
-3-5i
Step-by-step explanation:
Its 3,167 hope this helped
The value of z-score for a score that is three standard deviations above the mean is 3.
In this question,
A z-score measures exactly how many standard deviations a data point is above or below the mean. It allows us to calculate the probability of a score occurring within our normal distribution and enables us to compare two scores that are from different normal distributions.
Let x be the score
let μ be the mean and
let σ be the standard deviations
Now, x = μ + 3σ
The formula of z-score is

⇒ 
⇒ 
⇒ 
Hence we can conclude that the value of z-score for a score that is three standard deviations above the mean is 3.
Learn more about z-score here
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