S^2+4s-45=0 the solution for s=_____

Please help! Thanks !

s^2+4s-45=0
split the middle term 4s into -9s+5s
s^2-9s+5s-45=0
take s common from the first two terms and -5 from the last two terms to get
s(s+9)-5(s+9)=0
take (s+9) common from both terms to get
(s+9)(s-5)=0
ie either(s+9)=0 or (s-5)=0
if s+9=0 then s=-9
and if s-5=0, then s=5
ie, s=-9 or s=5.Good luck!

s^2+4s-45=0
= (s+9) (s-5)
s=-9 s=5