Answer:
11.5
The sample standard deviation measures the spread of a data distribution of the sample. It is usually used to estimate the population standard deviation
2x^3y+18xy-10x^2y-90y
= 2xy(x^2 + 9)- 10y(x^2 + 9)
= (x^2 + 9)(2xy - 10y)
= (x^2 + 9) 2y(x - 5)
= 2y (x^2 + 9) (x - 5)
To factor completely 18b - 32, we factor out the common factor of the two terms and divide each of term by the common factor.
18b - 32 = 2(18b/2 - 32/2) = 2(9b - 16)
