
850 twelveinch square tiles will be used to tile two square floors of a house. The sides of the first floor are ten feet longer than the sides of the second floor. How long are the sides of each floor?
Answer:The first floor is 25 feet square, and the second floor is 15 feet square. Here's how you solve it. Let x represent the length of the side of the second floor. Then the area of the second floor is x² square feet. The length of the side of the first floor is (x+10) feet. So the area of the first floor is (x+10)² square feet. The total area, 850 square feet, can be represented by the following equation:
So x is either 15 or it is negative twenty five. Negative answers don't make sense, so x=15. The answer follows. 
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