How do you factor #2x^2-98#?

1 Answer
Mar 20, 2018

Answer:

#2(x-7)(x+7)#

Explanation:

There's a common factor of 2 for both terms, so let's pull that out:
#2(x^2 - 49) #

Now, we know that #49 = 7^2#, which means that we can use difference of squares! The difference of squares formula is
#a^2 - b^2 = (a-b)(a+b) #

With #a = x# and #b = 7#, this tells us that
#x^2 - 49 = x^2 - 7^2 = (x-7)(x+7)#

so our final factorization is
#2x^2 - 98 = 2(x-7)(x+7) #