Help please I don't understand

Select the correct answer from each drop-down menu. a system of equations and its solution are given below. system a complete the sentences to explain what steps were followed to obtain the system of equations below. system b to get system b, the equation in system a was replaced by the sum of that equation and times the equation. the solution to system b the same as the solution to system a.]

What is the the area of this triangle expressed as a monomial?

Which of the following sets represents mun? (2,5,8) (4,7) (3,4,6,7,9) {3,6,9