SOLUTION: the cube of a number decreased by seven is four times the number

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Question 1194004: the cube of a number decreased by seven is four times the number
Found 3 solutions by math_tutor2020, ikleyn, Alan3354:
Answer by math_tutor2020(3816) About Me  (Show Source):
You can put this solution on YOUR website!

x = some unknown number
x^3 = the cube of a number
x^3 - 7 = decrease by 7
4x = four times the number

The given sentence translates to the equation x^3-7 = 4x

To solve this equation, you'll need to use graphing software. Cubic equations are notoriously difficult to solve by hand. Though some special crafted cubics are an exception.

Answer by ikleyn(52775) About Me  (Show Source):
You can put this solution on YOUR website!
.

This sentence is mathematically ambiguous, since another reading is possible


    %28x-7%29%5E3 = 4x.



Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
x = ~2.589132685188605 is the only real zero