What is the the vertex of $y=2x^2+15x -2$ ?

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Answer 1 · 2016-02-28T11:21:44

$x_("vertex")=-3.75$

I will let you work out $y_("vertex")$

Tony B Tony B

Given: $" "y=2x^2+15x-2$

A quick way of finding $x_("vertex")$ is as follows:

Write as $" "y=2(x^2+15/2x)-2$

Now apply : $" "(-1/2)xx15/2 = -15/4 = 3.75$

$color(blue)(x_"vertex"=-3.75)$
'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Now substitute back into the original equation to find $y_("vertex")$

What is the the vertex of y=2x^2+15x -2 y=2x^2+15x -2 ?