How do you simplify the product #(2x - 5)(x + 4)# and write it in standard form?

2 Answers

Answer:

#2x^2 + 3x - 20#

Explanation:

#(2x - 5 ) ( x + 4 )#

#2x xx x = 2x^2#

#2x xx 4 = 8x#

#-5 xx x = -5x#

#-5 xx 4 = -20#

#8x - 5x = 3x#

The answer is #2x^2 + 3x - 20#

Mar 31, 2017

Answer:

#(2x-5)(x+4)=color(blue)(2x^2+3x-20)#

Explanation:

Expand:

#(2x-5)(x+4)#

When multiplying two binomials, use the FOIL method as shown below. Then combine like terms and simplify, which will result in the standard form for a quadratic equation, #ax^2+bx+c#.

http://www.mesacc.edu/~scotz47781/mat120/notes/polynomials/foil_method/foil_method.html

#(2x-5)(x+4)#, where #ax=2x#, #b=-5#, #cx=x#, #d=4#.

Carry out the FOIL method for two multiplying binomials.

#(2x-5)(x+4)=2x*x+2x*4+(-5)*x+(-5*4)#

#(2x-5)(x+4)=2x^2+8x-5x-20#

Combine like terms.

#(2x-5)(x+4)=2x^2+8x-5x-20#

Simplify.

#(2x-5)(x+4)=color(blue)(2x^2+3x-20)##lArr# standard form