Question

z^4+10z^2+9

Answer 1

make the substitution t = z^2 so the equation becomes
\[t^2+10t+9\] then factorise it.

Answer 2

once finished replace t with z^2. do you see?

Answer 3

t^2 + 9t + 1t + 9
t(t + 9) +1(t + 9)
(t + 1) (t + 9)
now put t = z^2, we get
(z^2 + 1) (z^2 + 9)

Answer 4

When you factorise you look for factors of 9 that when added give you 10; so htats +1 and +9 so the factorisation is (t+1)(t+9)
now do a straight substitution: t for z^2
that gives \[(z^2+1)(x^2+9)\] as an answer as above.

Answer 5

ha I types x in the second bracket. So used to typing x. make it a z,lol

Answer 6

our medals pls ... :))