Persamaan garis lurus yang saling sejajar adalah dua persamaan garis lurus yang memiliki gradien atau kemiringan sama besar tetapi memiliki titik yang berbeda. Sehingga kedua garis tersebut tidak akan bertemu.[br][center][img width=62,height=22]data:image/png;base64,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[/img][/center]Contoh dari persamaan garis lurus yang saling sejajar adalah persamaan garis lurus [img width=88,height=22]data:image/png;base64,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[/img] dan persamaan garis lurus [img width=88,height=22]data:image/png;base64,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[/img]. Hal ini ditunjukkan oleh gradien dari kedua garis yang sama yaitu [img width=21,height=22]data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABUAAAAWCAMAAAAYXScKAAAAAXNSR0IArs4c6QAAAEJQTFRFAAAAAAAAAAA6ADqQAGa2OgAAOjqQOma2OpC2OpDbZgAAZpDbZrb/kDoAtmYAtpBm25A62////7Zm/9uQ//+2///bFsjmZAAAAAF0Uk5TAEDm2GYAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAAZdEVYdFNvZnR3YXJlAE1pY3Jvc29mdCBPZmZpY2V/7TVxAAAAVUlEQVQoU2NgGDggys/KyMSNZr8oL4cggwAjDxZniXBxYhEVZsWmlo8FqFSUlxEKmAVBOgXYwBQqEGDHIigEFBRmR1MpDNIugOYGqB3YXDZwIYtqMwA4PgIxnuPSqAAAAABJRU5ErkJggg==[/img] namun memiliki titik atau persamaan yang berbeda.[br]