Answer:
(3x-5)(3x+5)
Step-by-step explanation:
When you multiply a binomial out (ax+b), you get the form ax^2 + bx + c.
9x^2 + 15x - 15x -25
9x^2 - 25
The middle terms here cancel out because the signs are opposite each other.
(This will hold true for any binomial with opposite b values)