Question 406473
solve: 
x^2-13x+42=0
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Think of two numbers whose product is 42
and whose sum = -13
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The numbers are -6 and -7
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Rewrite the equation replacing -13x by -6x-7x
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x^2-6x-7x+42 = 0
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Factor:
x(x-6)-7(x-6) = 0
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(x-6)(x-7) = 0
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x = 6 or x = 7
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Cheers,
Stan H.
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