Übersicht

`16v+7 = 15v+1 || -15v `

`v+7 = 1 || -7 `

`v = -6 || :4 `

Probe:

`16*(-6)+7 = 15*(-6)+1 `

`-96+7 = -90+1 ` `-89 = -89 `✔✔

`=> L={-6} `