Answer
$(3x-5-6y)(3x-5+6y)$
Work Step by Step
The product of a binomial sum and a binomial difference is: $(A+B)(A-B)=A^2-B^2$.
The square of a binomial sum is: $(A+B)^2=A^2+2AB+B^2$.
The square of a binomial difference is: $(A-B)^2=A^2-2AB+B^2$.
Hence here: $9x^2-30x+25-36y^2=\\=(3x)^2-2\cdot5\cdot3x+5^2-(6y)^2=\\=(3x-5)^2-(6y)^2\\=(3x-5-6y)(3x-5+6y)$