1.Find triples of positive integers (x,y,z) such that xyz+xy+yz+xz+x+y+z=243.
im thinking of using congruence modulo.
Write it as $\displaystyle (1+x)(1+y)(1+z) = 244$, and then think of the possible ways of factoring 244.
Edit. Same problem was already answered in another thread.
Why do you and "redcherry" post all the same problems?
I smell spam.
I answered the very same question yesterday here
And then there's this problem and that problem... given that you two have registered almost at the same time, something weird is going on.
They might be classmates that don't know each other, or same class, but different section/teacher, or ... the problem might be coming from the same textbook ... Wouldn't quite make sense though if it's spam since Bruno answered on that last link before nh149's post