SOLUTION: find the whole number such that four times the number subtracted from the three times square of the number makes 15

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Question 709670: find the whole number such that four times the number subtracted from the three times square of the number makes 15
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
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find the whole number such that four times the number subtracted from the three times square of the number makes 15
:
3n^2 - 4n = 15
arrange as a quadratic equation
3n^2 - 4n - 15 = 0
Factors to
(3n+5)(n-3) = 0
only the whole number solution here
n = 3
:
Check in the original problem: 3(3^2) - 4(3) =