Yes
factor out the 2z^2 in each term
(2z^2)(z^2-5z+4)
factor some more
z^2-5z+4
find what 2 numbers multiply to get 4 and add to get -5
the numbers are -1 and -4
(z-1)(z-4)
the factored form is
(2z^2)(z-1)(z-4)
-2(2x-1)(x+3) = ((-2)2x - (-2)(-1))(x+3) = (-4x-2)(x+3)
No, because if he runs 7/30 mile each day he will run 210 miles each week because he is running 30 miles every day so he has to run 7/4.28 miles each day of the week to get 30 miles each week.