The Square of a positive integer is equal to the sum of the integer and 12. Find the integer

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The Square of a positive integer is equal to the sum of the integer and 12. Find the integer

Let the integer be x.

• The sum of the integer and 12 is written as x + 12.
• The square of a positive integer is written as x^2.

We set these equal to each other:
x^2 = x + 12

Subtract x + 12 from each side:
x^2 - x - 12 = 0

We have a quadratic function. Run it through our search engine and we get x = 3 and x = -4.
The problem asks for a positive integer, so we have x = 3