Uma umugqa oqondile udlula emaphuzwini (4,2) no (8,6) khona-ke unqamula kuphi i-x-axis? Chaza impendulo yakho.
Okokuqala, kufanele ubale i-gradient yomugqa ngokuthola ushintsho ku-y phezu koshintsho ku-x. Kulokhu, phakathi kwephuzu lokuqala nephuzu lesibili i-y-coordinate ikhula ngo-6-2=4 kanti i-x-coordinate ikhula ngo-8-4=4, ngakho-ke i-gradient ingu-4/4=1. Sibheka umugqa oqondile onokulingana y=x+c ngenani elithile le-c, esingalithola ngokufaka elinye lamaphuzu ethu, isibonelo, 4=2+c, ngakho-ke u-c kufanele abe ngu-2, futhi ukulingana komugqa ngu-y=x+2. Lapho umugqa unqamula i-x axis khona-ke i-y coordinate yawo ingu-0. Ngakho-ke kulokhu umugqa unqamula i-x-axis ku-x=-2.