Question 542963
a^2 + b^2 = c^2
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x^2 + (x+9)^2 = 45^2
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x^2 + x^2+18x+81 = 45^2
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2x^2 + 18x + 81 = 45^2
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2x^2 + 18x - 1944 = 0
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2(x-27)(x+36)
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x= -36
x= 27
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now since a lenght cannot be a negative, the answer is 27
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check
27^2 + 36^2 = 45^2
2025= 2025
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