<PRE><B>Question 551778</B>
If the answer is 6, then when we replace x with 6, the answer should be 0, right?  


x^2 + x - 42 = 0...This is your quadratic equation.


Let x = 6


(6)^2 + 6 - 42 = 0


36 + 6 - 42 = 0


42 - 42 = 0


0 = 0...IT CHECKS!!!


Yes, the answer is x = 6.


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