how can i defeat Houndoom (the one for Karen) in Heartgold version?

You have a good team and Typhlosion has Earthquake which would work against Hellgar/Houndoom being a fire type it's weak to ground attacks as well Seadra's fire attacks Waterfall which can make the target flinch if it doesn't KO it already but Surf and Brine are great attacks to use against it as well also maybe you could trying Nidoking with it's whirlpool and have it be trapped in the vortex and it loses HP every turn...and you try to switch it with Typhlosion or Seadra because you have a nice team and you have a lot of Hellgar/Houndoom's weaknesses in this team but considering it's a 47 also it might be good to level up some of these Pokemon a little maybe one or two levels or maybe give one of the Pokemon Carbos if you have them because that raises that Pokemon's Speed Stat also I suggest to carry some revives to revive fainted Pokemon and maybe some type of potions to restore HP or maybe even a Full Restore anyway hope I helped.