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40 votes
40 votes
The cube less the square of a number is twice the number. If x is a positive integer, what is its value

User Shay Shmeltzer
by
3.3k points

1 Answer

28 votes
28 votes

Answer:

2

Explanation:

let 'x' = number

x³ - x² = 2x

x³- x² - 2x = 0

x(x² - x - 2) = 0

x(x - 2)(x + 1) = 0

x = -1, 0, 2

the only positive solution is the number 2

User Allen Lavoie
by
2.6k points