SOLUTION: Three sides of a right-angled triangle are x, x-2 and x+5. What is the value of x?

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Question 862419: Three sides of a right-angled triangle are x, x-2 and x+5. What is the value of x?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Three sides of a right-angled triangle are x, x-2 and x+5. What is the value of x?
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Equation:
x^2 + (x-2)^2 = (x+5)^2
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x^2 + x^2 -4x + 4 = x^2 + 10x + 25
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x^2 -14x - 21 = 0
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x = [14 +- sqrt(14^2-4*1*-21)]/2
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x = [14 +- sqrt(280)]/2
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x = [14 + 16.73]/2
Positive solution:
x = 15.37
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Cheers,
Stan H.
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