If f(x)= x-5, then what is f(2)

Determine the mean and variance of the random variable with the following probability mass function. f(x)=( 729divided by 91) (1 divided by 9) superscript x baseline comma x equals 1,2,3 round your answers to three decimal places (e.g. 98.765).

Simply 8x squared + 5(7x squared- x) - 2x =

One line passes through (-7,-4) and (5,4) . another line passes through the point (-4,6) and (6,-9)