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Question 362333: The sum of two numbers is 18 and the sum of their squares is 170. Taking one number as x, form an equation and solve it to find the numbers.
How do I set this up and solve.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! The sum of two numbers is 18 and the sum of their squares is 170. Taking one number as x, form an equation and solve it to find the numbers.
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Equations:
x + y = 18
x^2 + y^2 = 170
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Substitute and solve for "x":
x^2 + (18-x)^2 = 170
x^2 + 18^2 - 36x + x^2 = 170
2x^2 -36x + 154 = 0
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x^2 - 18x + 77 = 0
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(x-11)(x-7) = 0
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If x = 11, y = 7
If x = 7, y = 11
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Take your choice.
The numbers are 7 and 11
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Cheers,
Stan H.
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