Answer:
The missing factor is 5y-9
5y^2-4y-9=(y+1)(5y-9)
Step-by-step explanation:
We are given this expression:
[tex]5y^{2}-4y-9[/tex]
Now let us factorise it using AC method of factorisation.
First taking product of 5 and -9
5*(-9)=-45
NOw we have to find two factors of -45 that add up to give -4
Two such factors are -9 and 5
So replacing -4y by -9y+5y,
[tex]5y^{2}-9y+5y-9[/tex]
Factoring by grouping,
[tex]y(5y-9)+1(5y-9)[/tex]
[tex](y+1)(5y-9)[/tex]
So the missing factor will be 5y-9