Can you show how you get your answers? The first problem reduces to a quadratic equation. The second problem reduces to an equation of fourth degree, but after cancellation it also becomes a quadratic equation.
(n!)/((n-2)!(n-(n-2))!)=6 - Wolfram|Alpha
Looking back on my cellphones wolfram application history it was a transcription error after all.(for 43)
((n+2)!/(4!(&# 40;n-2)!))=6((n!)&# 41;/(2!(n-2)!) - Wolfram|Alpha