the vertex of this parabola is at (4,-3). When the x-value is 5, the y-value is -6. what is the coefficient of the squared expression in the parabola's equation
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Answer:
Step-by-step explanation:
The work form of this upside down parabola is
[tex]y=-|a|(x-h)^2+k[/tex]
It's VERY important that you remember that the negative value there in front of the absolute value of a just means that the parabola is upside down. a itself will not be negative (and we know that because of the absolute value symbols there!). Filling in the x, y, h, and k values we were given allows us to solve for the |a|:
[tex]-6=-|a|(5-4)^2-3[/tex] and
[tex]-6=-|a|(1)^2-3[/tex] and
[tex]-6=-|a|1-3[/tex] and
[tex]-6=-|a|(-2)[/tex] and
3 = -|a|
Again, the negative simply tells us the parabola is upside down, so the absolute value of a = 3, choice c.