Identify the vertex, focus, axis of symmetry, and directrix for the parabola
Decide which of the two standard forms applies. The squared variable is , so the parabola opens vertically. That fixes the template as
If were the squared variable the parabola would open sideways and every formula below would swap roles.
Read off , and by matching term for term. Comparing with the template gives , and , so
Since the parabola opens upward.
The vertex is . Straight from the match, the vertex is .
The focus sits units from the vertex along the axis. For a vertical parabola the focus is :
The directrix sits units on the other side, and the axis passes through both. The axis of symmetry is the vertical line through the vertex, . The directrix is the horizontal line , i.e. the -axis.
Verify with the focus–directrix definition. Take : , so the point really is on the parabola. Its distance to the focus is , and its distance to the directrix is also . Equal distances confirm both the focus and the directrix.
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