SOLUTION: If {{{x^2}}} is added to x, the sum is 42. What could be the value of x?

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Question 594306: If x%5E2 is added to x, the sum is 42. What could be the value of x?
Answer by llorton(14) About Me  (Show Source):
You can put this solution on YOUR website!
x^2 + x = 42
x^2 + x - 42 = 42 - 42 = 0
We can factor the above quadratic by inspection as:
x^2 + x - 42 = (x + 7)(x - 6) = 0
x + 7 = 0 x - 6 = 0
x = -7 x = 6
Both values satisfy the requirement:
(-7)^2 + (-7) = 49 - 7 = 42
6^2 + 6 = 36 + 6 = 42