SOLUTION: Let a and b be the solutions to 7x^2 + x - 5 = 0. Compute (a - 4) + (b - 4).

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Question 1209226: Let a and b be the solutions to 7x^2 + x - 5 = 0. Compute (a - 4) + (b - 4).
Answer by ikleyn(52781) About Me  (Show Source):
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Let a and b be the solutions to 7x^2 + x - 5 = 0. Compute (a - 4) + (b - 4).
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(a-4) + (b-4) = (a+b) - 8.


For (a+b), according to the Vieta's theorem, we hasve

    a + b = -1%2F7.


Therefore,  (a-4) + (b-4) = (a+b) -8 = -1%2F7 - 8 = -81%2F7.    ANSWER

Solved.