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A magician asks a volunteer to think of two different positive integers without telling her what they are. She then asks him to calculate x, the sum of the larger number with the square of the smaller, and y, the difference between the numbers. The volunteer tells her that x = 9 and y = 3. Find the original numbers.

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Answer: 2 and 5.

Step-by-step explanation: We can use algebra to solve for the original numbers. Let's call the smaller number "a" and the larger number "b". From the information given, we know that:

x = b + a^2

y = b - a

The volunteer tells the magician that x = 9 and y = 3. So we can use these values to create a system of equations:

b + a^2 = 9

b - a = 3

To solve for the original numbers, we can first add the two equations together to eliminate b:

a^2 + 2a + 2 = 12

a^2 + 2a = 10

a^2 + 2a - 10 = 0

(a + 5)(a - 2) = 0

This tells us that the two solutions for a are -5 and 2. But since a is a positive integer, we know that it must be 2.

We can now substitute this value of "a" back into the original equations to find "b":

b + a^2 = 9

b + 2^2 = 9

b + 4 = 9

b = 5

So the original numbers are 2 and 5.

User Pawel Furmaniak
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