How do you simplify #(x - 5)(x+5)#?

1 Answer
Apr 19, 2018

Answer:

#x^2-25#

Explanation:

This is an example of DOTS: the Difference Of Two Squares.

When we have two brackets where one is pos and one is neg with the same number, we can use this method:

DOTS allows us to cancel any x values, like so:

#(x-5)(x+5)#
#=x^2+5x-5x-25#

You can see here that due to the signs and the numbers being the same, the #+5x-5x# cancel each other out to equal #0#.

#=x^2-25#

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