David deposits $1,000 into a savings account that earns simple interest at an annual rate of 5%. He plans to keep the money in the account for 3 years. After 3 years, he withdraws the money and buys a square piece of land with the total amount. If the price per square meter of the land is $50, what is the side length of the land he can purchase? Let's think step by step and output the final answer within \boxed{}.
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