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1 vote
Find the minimum or maximum y-value for f(x)=3x^2+12x+4.

2 Answers

4 votes
The vertex is (-2,-8)
So the y-value would be -8
User Ctuffli
by
4.0k points
3 votes


\bf \huge \red{ANSWER}

For the function f(x) =
{3x}^(2) + 12x + 4

, we need to find the vertex. The vertex is found by first finding
x, and then substituting for
x in the function.


\bf \huge \blue{Finding \: x}


x = ( - b)/(2a)

where b is the coefficient of the
x term and a is the coefficient of the
{x}^(2) term.


x = \frac{ - 12}{ {2}^(3) }


x = - 2


\bf \huge \green{finding \: y}

To find


y

, substitute for


x

in the given function


y = {3}^{ {( - 2}^(2)) } + {12}^(( - 2)) + 4


y = 12 - 24 + 4


y = - 16


\bf \huge \purple{vertex}

The vertex is
( - 2 - 16)

Since the coefficient of the
{x}^(2)

term is positive, we have a minimum.

The minimum is at -16.

User GilZ
by
4.2k points