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Parabolas do have a focus point Example: Find the focus point on the parabola: y = 2X2 There are two steps to the process. The first is to move the coefficients to the Y The second step is to factor a 4 out of the Y coefficient (who knows why a 4 works for this, but it does) What's left as the Y coefficient is the distance Step 1 Step 2: So the distance from the bottom of the "U" of the parabola to the focus point is 1/8 unit. Let's try another... Example: Find the focus point of the equation: Y = 8(X - 3)2 + 2 Step 1: Move the 8 away from the X 2 term Step 2: Factor the mysterious 4 out of the Y coefficient The distance from the bottom of the "U" (called the vertex) to the focus point is 1/32. Draw a line below the vertex of the parabola the same distance as the distance to the focus. Here's the deal. From any point on the parabola, it's the same distance to the focus point as it is to the closest point on the line we just drew ... If the X2 term has a minus sign in front of it, the "U" is upside down. That would make the focus point below the parabola vertex and the horizontal line above it ... But everything would still work the same. We could even reverse the X and Y. Example: Find the focus point of: X = 2Y2 Since this one is "sideways," move the coefficient To the X term and factor out the magic 4. So the focus point is 1/8 unit to the right of the vertex of the "U" And the line is 1/8 unit to the left of the vertex of the "U." THE DIRECTRIX