Apply the identity $a^{2} - b^{2} = (a + b)(a - b)$ to factor $x^{2} - 25$.
A$x(x - 25)$
B$(x - 5)^{2}$
C$(x + 5)(x - 5)$
D$(x - 25)(x + 1)$
Answer & Solution
Correct answer: C. $(x + 5)(x - 5)$
With $a = x$, $b = 5$: $x^{2} - 5^{2} = (x + 5)(x - 5)$.
- Trap A is $(x - 5)^{2} = x^2 - 10x + 25$, different.
- Trap C/D miscompute.
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