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We know that when A = 0 and B and C are nonzero values, the equation By2 + Cx + Dy + F = 0 represents a parabola that opens left or right.

As with the equation Ax2 + Cx + Dy + F = 0, which we studied earlier, the equation By2 + Cx + Dy + F = 0 does not provide us with enough information to easily draw a graph of a parabola.

Remember that we used a method called completing the square to rewrite the equation Ax2 + Cx + Dy + F = 0 into standard form for parabolas that open up or down: y - k = a(x - h)2.

Similarly, we use this method again to rewrite the equation By2 + Cx + Dy + F = 0 into the standard form for parabolas that open left or right,  x - h = a(y - k)2.

As before, the coordinates (h, k) denote the vertex of the parabola, and a descibes the shape and direction of the parabola.

Using the same steps as before, let's look at a few examples to see how this is done.

Summary of Steps

STEP 1:	Rearrange the equation to prepare to complete the square.
STEP 2:	Factor the coefficient of the squared term out of all terms on that side of the equation.
STEP 3:	Complete the square and add the necessary number to both sides of the equation.
STEP 4:	Simplify the equation.
STEP 5:	Divide, factor and/or rearrange the equation to get an equation of the form x - h = a(y - k)2.
In the following quesions, you will practise converting the equations of parabolas from general form to standard form.