SOLUTION: A rectangular parking lot has a length that is 3 yards greater than the width. The area of the parking lot is 700 square yards. What is the length and the width?

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Question 452698: A rectangular parking lot has a length that is 3 yards greater than the width. The area of the parking lot is 700 square yards. What is the length and the width?
Answer by ilana(307) About Me  (Show Source):
You can put this solution on YOUR website!
Write an equation to represent the situation. Call the width x. Then the length is x + 3. So the area is length times width, or x*(x + 3).
x(x + 3) = 700
x^2 + 3x = 700
x^2 + 3x - 700 = 0
Use the Quadratic formula:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%28-3+%2B-+sqrt%28+3%5E2-4%2A1%2A-700%29+%29%29%2F%282%2A1%29+
x+=+%28-3+%2B-+sqrt%28+9%2B2800+%29%29%2F%282%29+
x+=+%28-3+%2B-+sqrt%28+2809+%29%29%2F%282%29+
x = 25
So the length is x + 3, or 28. The rectangle is 25 yards wide by 28 yards long. (You also could have factored x^2 + 3x - 700 into (x - 25)(x + 28) to get this answer.