No, there's definitely enough information to solve this problem. What you've done so far is great, but you've for some reason stopped five feet short...
As tkhunny said, the basic way to prove each of these is to use separate cases. The first three will be similar: show that it is true for all x >= 0,...
Hi. Sure someone here can help. That is never a problem. But 1st you need to tell us where you are stuck or what you have tried and then once we see...
I see that you are still practicing your times table as I suggested. Good job. One day you will get beyond the 5 table. Just keep trying, I know you...