Final answer:
Confidence before the 1929 stock market crash stemmed from economic growth and speculative investments based on credit. Despite warning signs, over-speculation persisted until the market collapsed, causing massive financial losses and contributing to the Great Depression.
Step-by-step explanation:
People felt confident before the stock market crash of 1929 due to a decade of economic prosperity that led to over-speculation and the use of credit to purchase stocks. The accessibility of credit allowed for risky investments with money that individuals did not have.
Warning signs, such as the downturn in September 1929 and the London Stock Exchange's collapse, did not deter investors' confidence as many continued to speculate. Even attempted interventions by big banks to stabilize the market proved unsuccessful. The stock market finally crashed, leading to significant financial loss and the onset of the Great Depression.