What is the vertex form of $y = (3 x - 2) (4 x + 1)$ $y=(3x - 2) (4x + 1)$ ?

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Answer 1 · 2018-08-11T03:47:51

$y = 12 {(x - .208)}^{2} - 2.52$ $y=12(x-.208)^2-2.52$

First put the function into standard form by foiling:

$y = 12 x^{2} - 5 x - 2$ $y=12x^2-5x-2$

Find the vertex: $x = - \frac{b}{2 a}$ $x=-b/(2a)$

$x = \frac{5}{24}$ $x=5/24$ = $.208$ $.208$

plug that into the original equation:

$\frac{300}{576} - \frac{25}{24} - 2$ $300/576-25/24-2$ = $- 2.52$ $-2.52$

vertex $(h, k)$ $(h,k)$ : ( $.208$ $.208$ , $- 2.52$ $-2.52$ )

put it into $y = a {(x - h)}^{2} + k$ $y=a(x-h)^2+k$ form:

$y = 12 {(x - .208)}^{2} - 2.52$ $y=12(x-.208)^2-2.52$
graph{y=12(x-.208)^2-2.52 [-10, 10, -5, 5]}

What is the vertex form of y=(3x−2)(4x+1)y=(3x - 2) (4x + 1) ?