[mzer]

Thanks. I can get there by truth table, but I was hoping to show something more like this...

(P -> R) ^ (Q->R) / (P v Q) -> R

(-P v R) ^ (-Q v R) ---(Conditional law)
(-P ^ -Q) v R ---(Distributive law)
-(P v Q) v R ---(de Morgan's law)
(P v Q) -> R ---(Conditional law)

I'm not sure what he really needs, perhaps a TT is enough, but the above is what I remember doing years ago, so that is what I was trying to help him do. Thanks again for your help.