Answer :

konrad509
[tex] 4y^2+54y-90=\\ 2(2y^2+27y-45)=\\ 2(2y^2+30y-3y-45)=\\ 2(2y(y+15)-3(y+15))=\\ 2(2y-3)(y+15)[/tex]
   4y²+54y-90
= 2(2y²+27y-45)
= 2(2y-3)(y+15)  <- this is the final answer. :)