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In order to find the vertex of a parabola, we use the following formula:
[tex]\bold{\displaystyle\frac{-b}{2a} }}[/tex]
Remember, a parabola looks like so:
[tex]\tt{y=ax^2+bx+c}[/tex]
Now we know what a and b stand for.
In this case, b is -4, and a is -1:
[tex]\hookrightarrow\sf{\displaystyle\frac{-(-4)}{2(-1)}[/tex]
Simplify:
[tex]\hookrightarrow\sf{\displaystyle\frac{4}{-2} }}[/tex]
Divide:
[tex]\hookrightarrow\sf{-2}[/tex]
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[tex]\mathbb{DiAmOnD}\\{\boxed{An~Emotional~And~Creative~Helper}}}}[/tex]
