been using hydrogen peroxide and baking soda for teeth whiten for 3 weeks but the are still yellow?

i have hydrogen peroxide that contin 6% i duilte it with equal water with baking soda i use it every day on day a time i mix the ingerdin and put it on my teeth for 1 minute i know that hydrogen peroxide is harmfull but i cant afford the dentist whitening i used crest white strips they didn't work so help
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I'm not so sure it is that simple...or everyone would be doing it that way. If the whitening strips don't work for you it could be your teeth. Some peoples teeth are actually yellow, gray or opague in color. If this is the case, whitening will not work. Whitening removes the stains from the surface of the tooth, so if a persons teeth are not white underneath of the stains the whitening agents will have no effect. They can only remove stains, not change the actual color of your teeth.
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