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

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Answer 1 · 2015-12-05T23:55:40

The standard form is $y=-x^2+5x-12$ .

$y=(x+4)(2x-3)-3x^2$

The standard form for a quadratic equation is $ax^2+bx+c$ , where $a, b, and c$ are coefficients.

First Foil the two binomials.

![http://hubpages.com/education/Using-the-FOIL-Method-to-Expand-Products]( useruploads.socratic.org )

$(x+4)(2x-3)$

$a=x, b=4, c=2x, d=-3$

$(x+4)(2x-3)=ac+ad+bc+bd$

$(x+4)(2x-3)=(x*2x)+(x*-3)+(4*2x)+(4*-3)$

$(x+4)(2x-3)=(2x^2)+(-3x)+(8x)+(-12)$

Combine like terms.

$(x+4)(2x-3)=2x^2+5x-12$

Return to original equation, keeping the foiled results.

$y=2x^2+5x-12-3x^2$

Combine like terms.

$y=2x^2-3x^2+5x-12$

$y=-x^2+5x-12$

What is the standard form of y=(x+4)(2x-3) -3x^2y=(x+4)(2x-3) -3x^2?