How would I make the velocity go in the way the player is facing?

So, im trying to make a knockback system and im using a body velocity to make the "target" get knocked back a few studs. However I want the target to get knocked in the opposite direction of where the player is facing. The "Player" is the one hitting the target.. As of now, I dont know how I should achieve this. this is what I have currently

BV.Velocity = hitHRP.CFrame.lookVector*-10

hitHRP is the target's HumanoidRootPart