Lettervormen herleiden

Herleid de lettervormen

\(2x+3xy+x+4xy-2x\)

\(\begin{align}2x+3xy+x+4xy-2x&=2.x+3.xy+1.x+4.xy-2.x\\&=2.x+1.x-2.x+3.xy+4.xy\\&=x+7xy\\\\ \end{align}\)