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4 votes
4 votes
The difference between a number and its square is 42 find the number

User Bungrudi
by
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1 Answer

13 votes
13 votes

Answer:

x = 7 or -6

Explanation:

Let a number be x.

Its square = x²

x - x² = 42

-x² + x - 42 = 0

-(x² - x + 42) = 0

x² - x + 42 = 0

(x - 7)(x + 6) = 0

x - 7 = 0 or x + 6 = 0

x = 7 or x = -6

User Dan Billings
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2.9k points