What is the standard form of #y= (x+2) (4x+1) #?

2 Answers
Dec 5, 2015

#y=4x^2+9x+2#

Explanation:

The "standard form" for a quadratic equation is
#color(white)("XXX")y=ax^2+bx+c#
with constants #a, b, c#

Given #y=(x+2)(4x+1)#
we can convert this into standard form by simply multiplying the two factors on the right side:
#color(white)("XXX")(x+2)(4x+1)=4x^2+9x+2#

Dec 5, 2015

#y=4x^2+9x+2#

Explanation:

#y=(x+2)(4x+1)#

Foil the two binomials.

http://hubpages.com/education/Using-the-FOIL-Method-to-Expand-Products

#a=x, b=2, c=4x, d=1#

#y=(x*4x)+(x*1)+(2*4x)+(2*1)#

Simplify.

#y=4x^2+x+8x+2#

Combine like terms.

#y=4x^2+9x+2#