7. Modus dari rata-rata 86.7.6.86.7.9.6896810.6.8 berikut adalah B. 7 C.8 D.9 8. Nilai a dan b pada persamaan 2a-2b-6=0 dan 2a-6b+2=0 adalah A (-2,15) B. (5,-2) (5,2) C (30,15)

7. C 8. B

7. The mode of a set of numbers is the number that appears most frequently. In the given set {6, 8, 6, 8, 6, 8, 8, 6, 8, 8}, the number 8 appears most frequently. Therefore, the mode is 8. 8. To find the values of and that satisfy the system of equations and , we can solve the system of equations. The solution to the system is and , which corresponds to the point (3.5, 0.5). However, this option is not provided in the choices. On further inspection, it seems there might be an the provided options or the equations. The closest option to the solution is B. (5,-2).