Stuck in a pattern

Stuck in a pattern. 16 stitches on needle. Left Neck Shaping - bind off 5 sts, work in garter st to end - 11 sts.
HOW ???

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When you bind off the 5sts there will be 11sts remaining on the needle out of the 16 original stitches: one stitch on the right hand needle and 10 on the left hand needle. Finish the row by knitting across those 10sts.
Here’s a video for the often used stitch-over-stitch bind off.

In the video, all the sts on the needle are bound off but you will only be binding off the first 5sts, then continuing to knit across the row.