the substitution and elimination method

good afternoon maam!!!!

uhmm...at first,,i really dont know how to use the substitution method,,,.that's why on the 2nd day,,i carefully analyze each step...and after that,,i was able to catch on and i realyze that it's not that hard...after that lesson..,we proceed to another lesson,,the elimination method...for me,the elimination method is easier than the substitution method...

by the way,,maam,,thank you 4 explaining...