Answer:
[tex](3x-5)(3x+5)[/tex]
Step-by-step explanation:
Difference of squares states that:
[tex]a^2-b^2=(a-b)(a+b)[/tex]
In this case...
[tex]a^2=9x^2\\\sqrt{a^2}=\sqrt{9x^2}\ (take\ the\ square\ root\ of\ both\ sides)\\a=3x[/tex]
[tex]b^2=25\\\sqrt{b^2}=\sqrt{25}\ (take\ the\ square\ root\ of\ both\ sides)\\b=5[/tex]
This means that...
[tex]9x^2-25=(3x-5)(3x+5)[/tex]
