7xy2 + 14x4y - 28xy
What is 7xy(y + 2x3 - 4)
2y2 - 2z - ay2 + az
What is (2-a)(y2-z)
x2 - 17x + 72
What is (x-8)(x-9)
x2 - 36y4
What is (x-6y2)(x+6y2)
10(2a-1)2 - 19(2a-1) - 15
What is 2(5a - 1)(4a - 7)