## Differential Equations and Linear Algebra (4th Edition)

$4x+(-7)y=5(3, −1, 2, 5)-7(−1, 2, 9, −2)=(15,-5,10,25)+(7,-14,-63,14)=(22,-19,-53,39)$ The additive inverse of $(x,y,z,w)$ is $(-x,-y,-z,-w)$, thus here the additive inverse is $(-22,19,53,-39)$.