# Finding the focus and directrix of a parabola?

• May 26th 2010, 08:02 PM
Incursion
Finding the focus and directrix of a parabola?
How do you find the focus and directrix of a parabola when given an equation in X^2=4PY form?
EX) Find the focus and directrix of the parabola 10Y=7X^2
• May 26th 2010, 08:12 PM
pickslides
You might need to make your equation $10y=7x^2 \implies 7x^2=10y \implies x^2=\frac{10}{7}y\implies x^2=4\frac{10}{28}y$