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PLEASE HELP!

The equation of a parabola is y=1/2x^2+6x+23.


What is the equation of the directrix?


y = 5.5


y = 4.5


​y = 2​


​y = 0.5

2 Answers

5 votes

Answer: y=4.5 Just confirming

Explanation:

Just a test good luck

User Joanwolk
by
3.5k points
4 votes

Answer:

Explanation:

y = ½x² + 6x + 23

  = ½(x² + 12x) + 23

  = ½(x² + 12x + 6²) - ½(6²) + 23

  = ½(x+6)² + 5

vertex (-6,5)

focal length = 1/(4∙½) = ½

directrix: y = 5-½ = 4.5

User Ilia Yatsenko
by
3.9k points