How do you find a positive number whose square is 12 more than the number itself?

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Answer 1 · 2016-01-25T00:43:06

Translate the problem into an equation, and solve to find that the number is #4#

Translate the problem into an equation:
#x^2 = x+12#

Solve the quadratic equation:
#x^2 - x - 12 = 0#

Try factoring. If this does not work, we can use the quadratic formula:
#(x+3)(x-4) = 0#

#x = -3# or #x = 4#

Throw out the negative result:
#x = 4#