How do you simplify the product #(6x - 5)(3x + 1)# and write it in standard form?

2 Answers
Jun 3, 2018

Answer:

#18x^2-9x-5#

Explanation:

#"each term in the second bracket is multiplied by each"#
#"term in the first bracket"#

#=(color(red)(6x-5))(3x+1)#

#=color(red)(6x)(3x+1)color(red)(-5)(3x+1)larrcolor(blue)"distribute"#

#=(color(red)(6x)xx3x)+(color(red)(6x)xx1)+(color(red)(-5)xx3x)+(color(red)(-5)xx1)#

#=18x^2color(blue)(+6x)color(blue)(-15x)-5larrcolor(blue)"collect like terms"#

#=18x^2-9x-5larrcolor(magenta)"in standard form"#

Answer:

Try using the FOIL method (First, Outside, Inside, Last)
#18x^2-9x-5#

Explanation:

You have to multiply each term in the left bracket by each term in the right bracket. The easiest way to make sure you don't miss anything is to use a systematic method such as FOIL.
The FOIL method means selecting those pairs of numbers to multiply together
Eg. #(a+b)(c+d)=ac+ad+bc+bd#

Question #(6x-5)(3x+1)#
First: #6x*3x=18x^2#
Outside: #6x*1=6x#
Inside:#-5*3x=-15x#
Last: #-5*1=-5#
Now we add them together
#(6x-5)(3x+1)=18x^2+6x+(-15x)+(-5)#
#6x# and #-15x# are like terms so they simplify
leaving us with
#(6x-5)(3x+1)=18x^2-9x-5#