Persamaan garis lurus yang saling berhimpit adalah dua persamaan garis lurus yang memiliki titik dan gradien yang sama. Sehingga ketika dilihat secara sekilas akan terlihat menyatu padahal terdapat lebih dari satu garis. [br][center][img width=62,height=22]data:image/png;base64,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[/img][/center]Contoh persaman garis lurus yang saling berhimpit adalah persamaan garis lurus [img width=76,height=22]data:image/png;base64,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[/img] dan [img width=104,height=22]data:image/png;base64,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[/img]. Kedua persamaan ini memiliki titik dan gradien yang sama sehingga terlihat menyatu padahal terdapat dua garis, yaitu garis [img width=9,height=22]data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAkAAAAWCAMAAAAlz0ZsAAAAAXNSR0IArs4c6QAAAEtQTFRFAAAAAAAAAAA6AABmADpmADqQAGa2OgAAOgA6OpDbZgAAZrb/kDoAkNv/tmYAttv/tv//25A625Bm27Zm2////7Zm/9uQ//+2///bVz4oZAAAAAF0Uk5TAEDm2GYAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAAZdEVYdFNvZnR3YXJlAE1pY3Jvc29mdCBPZmZpY2V/7TVxAAAAT0lEQVQYV2NgIAUIsTOygdULsooIcoIY4lzcUAOEmXghLD5GRkZmAQgTopqBQYIHrBoIxDigyhhEoYqQlIlzYSiT4GMVgejkYuEnxa0MDAD0KAIwsE72KAAAAABJRU5ErkJggg==[/img] dan garis [img width=10,height=22]data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAoAAAAWCAMAAADO+P1vAAAAAXNSR0IArs4c6QAAAGNQTFRFAAAAAAAAAAA6AABmADpmADqQAGa2OgAAOgA6OgBmOma2OpC2OpDbZgAAZjoAZmYAZmaQZpDbZra2Zrb/kDoAkNv/tmYAtmY6tpCQttvbtv//2////7Zm/9uQ/9u2//+2///boWEvGgAAAAF0Uk5TAEDm2GYAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAAZdEVYdFNvZnR3YXJlAE1pY3Jvc29mdCBPZmZpY2V/7TVxAAAAV0lEQVQYV2NgoB2Q42NkEhKQBlogy84tLc/LA7JKjFWaQZ5XGMgCk7KcUiB5DlGIDEipsIIEPxvYVeKMLJIiIKUyXCCCGaRUBMiUZQcbJcvHyMgkSKr7Aa5DBCBDNVx7AAAAAElFTkSuQmCC[/img].