x²-25=(x+5)(x-5) a³-ab²=a(a²-b²) = a(a+b)(a-b)①m²-9n²= (m+3n)(m-3n)②ab³-4ab= ab(b-4)③(5x-3)²-16x= (5x+4√x-3)(5x-4√x-3)④16x^4-1= (4x²+1)(4x²...