Respuesta :

Multiplying two fractions is very easy: you need to multiply one numerator with the other, and one denominator with the other.

So, in your case, the answer is

[tex] \cfrac{x-1}{x+5} \cdot \cfrac{x+1}{x-5} = \cfrac{(x-1)(x+1)}{(x+5)(x-5)} [/tex]

Both expressions at numerator and denominator are in the form [tex] (a+b)(a-b) [/tex]. This is a known case, where the result is the difference of the squares:

[tex] (a+b)(a-b) = a^2-b^2[/tex]

So, the answer is

[tex] \cfrac{(x-1)(x+1)}{(x+5)(x-5)} = \cfrac{x^2-1}{x^2-25}[/tex]

11AnimalLover11
The equations are what’s known as “completing the squares,” which basically means that when you multiply it out, the middle cancels out

(x - 1)(x + 1)/(x + 5)(x - 5)
x^2 - x + x - 1/x^2 + 5x - 5x - 25
x^2 - 1/x^2 - 25

The answer is C

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