Respuesta :

[tex]\bf \textit{recall that }i^2=-1 \\\\[-0.35em] ~\dotfill\\\\ x^2+25\implies x^2+5^2\implies x^2-(-5^2)\implies x^2-(-1\cdot 5^2)\implies x^2-(i^2\cdot 5^2) \\\\\\ \stackrel{\textit{difference of squares}}{x^2-(5i)^2}\implies (x-5i)(x+5i)[/tex]

Answer:

The correct option is A.

Step-by-step explanation:

The given expression is

[tex]x^2+25[/tex]

[tex]x^2+5^2[/tex]

[tex]x^2-(-5^2)[/tex]

We know that [tex]i^2=-1[/tex].

Using this value the given expression can be written as

[tex]x^2-(i^25^2)[/tex]

[tex]x^2-(5i)^2)[/tex]              [tex][\because a^mb^m=(ab)^m][/tex]

[tex](x-5i)(x+5i)[/tex]             [tex][\because a^2-b^2=(a-b)(a+b)][/tex]

The given expression is equal to the expression (x-5i)(x+5i).

Therefore the correct option is A.

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