Lettervormen herleiden

Herleid de lettervormen

\(-2x+y-4x+y+x\)

\(\begin{align}-2x+y-4x+y+x&=-2.x+1.y-4.x+1.y+1.x\\&=-2.x-4.x+1.x+1.y+1.y\\&=-5x+2y\\\\ \end{align}\)