X-y-3z=-9
1 =-3x-1
x=5y-z +23 i need to find x, y and z with work

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Given the following sampling distribution of one mean with a sample size 49, from a normally distributed population,find the population standard deviation, o.79828588912497

Factor the polynomial, if possible. if the polynomial cannot be factored, write prime. 9n^3 + 27n^2 – 25n – 75