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

1 Answer
Dec 5, 2015

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

Explanation:

#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

#(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#