Brake line leak on 1996 Toyota Avalon

Had loss of brakes and thought it was master cylinder. But now I see a serious fluid leak in a line located under the drivers seat. Why would all brakes fail instead of just the rear (or front)?

Get Your Car Fixed at a RepairPal Certified Shop.
We certify shops based on expertise, quality work, and verified customer reviews
1 answer
Need to have a shop do a complete inspection of the brake lines and give you a estimate of repairs http://repairpal.com/directory?address=06443&car_brand_names=Toyota