equation for horizontal parabola

Question

mathmale · Answer

Depends upon how much detail you want to go into.  If y = x^2, the corresponding graph opens UPWARD, that is, in the positive y direction.  If we interchange y and x in the above equation, we get x = y^2, whose graph opens to the right, in the positive x direction.

pinknabastak · Answer

my paper just says wtire an equation for a horizontal parabola

mathmale · Answer

Well, that x = y^2 mentioned above is just about the simplest equation for a horizontal parabola.  Have you checked your textbook and notes for other examples?

pinknabastak · Answer

what about for a circle? @mathmale

mathmale · Answer

Dear PNBS,
We're dealing with what's called "conic sections."  Conic sections include circles, parabolas, ellipses and hyperbolas.  Mind looking up formulas and illustrations in your textbook or notes?

The most basic equation for a circle of radius r which is centered at the origin is
x^2 + y^2 = r^2.  If the center is at (h,k) instead, the equation of the circle becomes (x-h)^2 + (y-k)^2 = r^2.