Do you have the Bitcoin address for your Breadwallet? Instead of scanning a QR code, look for your actual address (the "1" followed by the random numbers and letters). You could probably find it in the receiving addresses part of the app, if it has one. It may also be in settings. Once you find it, go to your Coinbase account, click "Send Bitcoin" or whatever it may be called, and type in the address you found from Breadwallet. Do note, depending on how small of a fraction you bought, you may not even be able to send the Bitcoin, or you may lose a great deal of it to transaction fees.