f: \(\left(y-1\right)^2\)
e: =(x+y+5)(x+y-5)
\(d,15x^2y+20xy^2+25xy=5xy\left(3x+4y+5\right)\\ e,\left(x+y\right)^2-25=\left(x+y\right)^2-5^2=\left(x+y-5\right)\left(x+y+5\right)\\ f,1-2y+y^2=\left(1-y\right)^2\\ h,4x^2+8xy-3x-6y=\left(4x^2+8xy\right)-\left(3x+6y\right)=4x\left(x+2y\right)-3\left(x+2y\right)=\left(x+2y\right)\left(4x-3\right)\)