How to I find the solution to a system of equations by graphing?

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).

Layla answer 21 of the 25 questions on his history test correctly.what decimal represents the fraction of problem he answer incorrectly.

Afarm is to be built in the shape of quadrilateral abcd, as shown below. all four sides are equal. a rhombus abcd is shown with diagonal ac equal to 15.5 feet and diagonal bd equal to 13.2 feet. what is the area of the farm? pleas only pick from the 4 below 62 square feet 52.8 square feet 57.4 square feet 102.3 square feet