How do I "Find the vertex of the quadratic equation: y = 2x2 + 8x − 4."

Question

amistre64 · Answer

there are a few ways from very brunt mathing, to elequant techniques in form and design

amistre64 · Answer

what methods are you aware of?

anonymous · Answer

None of the above? how about we go with the easiest way to do it and remember it?

amistre64 · Answer

easiest way is to remember the general form of a quadratic as:
$$ax^2+bx+c$$
and remember that the value of the x component of the vertex is:$$x=-\frac{b}{2a}$$

amistre64 · Answer

the y component is just inserting the value of the x component into the equation and solving

amistre64 · Answer

y = 2x2 + 8x − 4

x = -8/(2*2) = -2
y = 2(-2)2 + 8(-2) − 4

vertex:  (-2, f(-2))

anonymous · Answer

f?

anonymous · Answer

$y=f(x)=2x^2+8x-4$

amistre64 · Answer

y = f(x)

y = f(-2)  simply means the value of the function at x=-2

anonymous · Answer

I am so confused 0.0

mertsj · Answer

Find the x coordinate of the vertex by using x = -b/2a = -8/4=-2
Plug that back in the find the y coordinate:  
$$2(-2)^2+8(-2)-4=2(4)-16+4=8-16-4=-12$$