How do you factor completely #2x^2-8#?

2 Answers
Mar 5, 2018

#color(brown)(2 * (x+ 2) * (x - 2)#

Explanation:

#2x^2 - 8 = 2x^2 - (2*2*2) = 2x^2 - (2 * 4)#

#x@^2 - 4# is in the form #a^2 - b^2 = (a+b) * (a - b)#

#:. => 2 * (x^2 - 4) = 2 * (x+ 2) * (x - 2)#

Mar 5, 2018

#2(x-2)(x+2)#

Explanation:

#"take out a "color(blue)"common factor of 2"#

#rArr2(x^2-4)#

#x^2-4larrcolor(blue)"is a difference of squares"#

#•color(white)(x)a^2-b^2=(a-b)(a+b)#

#rArrx^2-4=(x-2)(x+2)#

#rArr2x^2-8=2(x-2)(x+2)#