How do you simplify the expression (5x-2)^2?

2 Answers
Jun 17, 2017

25x^2-20x+4

Explanation:

To solve this problem first you rewrite as follows:

(color(blue)(5x)color(darkred)(-2))(color(red)(5x)color(green)(-2))

Then you proceed to FOIL it:

Where you multiply the color(blue)"first term" with the color(red)"outer term" then you multiply the color(blue)"first term" with the color(green)"inner term":

(color(blue)(5x))(color(red)(5x))=25x^2

(color(blue)(5x))(color(green)(-2))=-10x

Now you multiply the color(darkred)"last term" with the color(red)"outer term" then you multiply the color(darkred)"last term" with the color(green)"inner term":

color(darkred)((-2))(color(red)(5x))=-10x

color(darkred)((-2))(color(green)(-2))=4

Now combine them:

25x^2-10x-10x+4

Simplify:

25x^2-20x+4

Jun 17, 2017

25x^2-20x+4

Explanation:

"express " (5x-2)^2" as " (5x-2)(5x-2)

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

(color(red)(5x-2))(5x-2)

=color(red)(5x)(5x-2)color(red)(-2)(5x-2)

=(color(red)(5x)xx5x)+(color(red)(5x)xx-2)+(color(red)(-2)xx5x)+(color(red)(-2)xx-2)

=25x^2+(-10x)+(-10x)+4

=25x^2-10x-10x+4

=25x^2-20x+4