G(z)=(z−1)^5 −(z−1)^4 The polynomial function G is defined above. What is the product of the zeros of G?

I was doing SAT problems and I came across this one that I couldn't figure out. I attached the explain they gave me but it would be awesome if someone could explain it a little bit further. Thanks!

F(n + 1) = f(n) – 8. if f(1) = 100, what is f(6)?

In the following diagram it is given that dec,ab || dc, ad || eb, and ad is congruent to bc. a)why isn't abc a parallelogram even though it has a pair of parallel sides and a pair of congruent sides b)explain why be must be congruent to bc. further explain what type of triangle this makes triangle abc and what it tells you about angle 1 and angle 2c) finally why must angle 3 be congruent to angle 1? further, explain why we know that angle 3 is congruent to angle 2

What is the expression in factored form? -x^2 + 3x + 28 a. (x-7)(x-4) b. -(x-7)(x+4) c. (x+4)(x+7) d. -(x-4)(x+7)