Question

Find the vertex of the quadratic equation: y = 2x2 + 12x − 4.

(−3, 50)

(3, 50)

(−3, −22)

(−3, −58)

Answer 1

What's a vertex?

Answer 2

Hint: derivative

Answer 3

the vertex is where the curve changes from decreasing to increasing... or vice versa...

easist way is

\[x = -\frac{b}{2a}\]

in your equation you have a = 2 and b = 12

so

\[x = \frac{-12}{4}\]

simplify it to get the x value of the vertex.

then substitute it into the original equation to find the y value

Answer 4

I'm sorry....are you still confused?

Answer 5

lol sorry but yes.

Answer 6

what will x be ?

Answer 7

umm 3

Answer 8

can you tell me what
\[\frac{-12}{4}\]
is?

Answer 9

-3

Answer 10

great now that we know that \[x=-3\]
We want to know what y is

\[y = 2x^2 + 12x − 4\]
All you have to do is plug in
\[x=-3\] to the top equation and solve for y


After doing that you will get your
(x,y)

Answer 11

soo y= -22...?

Answer 12

yes
so it's
(-3,-22)