→r=5ˆi−4ˆj+6ˆk+t(3ˆi+7ˆj+2ˆk)→r=3ˆi+7ˆj+2ˆk+t(5ˆi−4ˆj+6ˆk)→r=5ˆi−4ˆj+6ˆk−t(5ˆi−4ˆj+6ˆk)→r=3ˆi+7ˆj+2ˆk+t(3ˆi+7ˆj+2ˆk)