How do you factor $25x^2n - 49$ ?

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Answer 1 · 2015-12-27T21:10:11

If $n$ is a positive constant, then this factorises as:

$25x^2n-49 = (5xsqrt(n)-7)(5xsqrt(n)+7)$

This question seems a little curious. Should the $n$ be there? Should it be $n^2$ ?

In any case, we can use the difference of squares identity:

$a^2-b^2 = (a-b)(a+b)$

with $a = 5xsqrt(n)$ and $b=7$ ...

$25x^2n-49$

$=(5xsqrt(n))^2 - 7^2$

$=(5xsqrt(n)-7)(5xsqrt(n)+7)$

How do you factor 25x^2n - 49 25x^2n - 49 ?