30 pts!

1. consider the linear system of equations y = 2/5x - 1 and y = 2/3x – 0.3
a) what is the solution to the system of equations?
(i found this to be (-2.8, -2)
b) verify the solution.
(no idea how to do this)

Based on what i know about mean, this doesn't add up.

Ian is in training for a national hot dog eating contest on the 4th of july. on his first day of training, he eats 4 hot dogs. each day, he plans to eat 110% of the number of hot dogs he ate the previous day. write an explicit formula that could be used to find the number of hot dogs ian will eat on any particular day.

The mean of 10 values is 19. if further 5 values areincluded the mean becomes 20. what is the meanthese five additional values? a) 10b) 15c) 11d) 22