EntityQ1332432· pop 16· linked from 39 articleselliptic coordinate systemSign in to savetwo-dimensional orthogonal coordinate systemConnectionsCartesian coordinate systemEntityorthogonal coordinate systemEntitybipolar coordinatesEntitygeometryEntitygeographic coordinate systemEntitymomentumEntityellipseEntitycoordinate systemEntitytrigonometric functionEntityhyperbolaEntitypolar coordinate systemEntityhyperbolic functionEntityspherical coordinate systemEntitypartial differential equationEntitycomplex planeEntityLaplace's equationEntityecliptic coordinate systemEntitycylindrical coordinate systemEntityfocusEntityHelmholtz equationEntityCategoriesEllipsesTwo-dimensional coordinate systems