How do you factor the expression 25x^2-6425x264?

1 Answer
Dec 8, 2017

25x^2-64 = (5x-8)(5x+8)25x264=(5x8)(5x+8)

Explanation:

The difference of squares identity can be written:

A^2-B^2=(A-B)(A+B)A2B2=(AB)(A+B)

In the given example, both 25x^2 = (5x)^225x2=(5x)2 and 64 = 8^264=82 are perfect squares. So we can put A=5xA=5x and B=8B=8 to find:

25x^2-64 = (5x)^2-8^2 = (5x-8)(5x+8)25x264=(5x)282=(5x8)(5x+8)