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Would anyone know the answer to this?

Would anyone know the answer to this?-example-1

2 Answers

7 votes
No sorry I have no idea what the answer should be here
User Chad Brown
by
7.3k points
5 votes

Answer: The mystery number is 5.5

5.5 converts to the fraction 11/2.

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Step-by-step explanation:

The phrasing "subtract 10 from the number, then square the result" leads to the expression
(\text{x}-10)^2

The phrasing "Square the number, then subtract 10 from the result" means we have
\text{x}^2-10

Set those expressions equal to one another so we can solve for x like shown in the steps below.


(\text{x}-10)^2 = \text{x}^2-10\\\\\text{x}^2-20\text{x}+100 = \text{x}^2-10\\\\-20\text{x}+100 = -10\\\\-20\text{x} = -10-100\\\\\text{x} = -110/(-20)\\\\\text{x}=11/2\\\\\text{x} = 5.5

The x^2 terms cancel out in the third step (since we subtract x^2 from both sides).

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Check:


(\text{x}-10)^2 = \text{x}^2-10\\\\(5.5-10)^2 = (5.5)^2-10\\\\(-4.5)^2 = (5.5)^2-10\\\\20.25 = 30.25-10\\\\20.25 = 20.25

The answer is confirmed.

User Jomafer
by
7.6k points