SOLUTION: The sum of an interger and its square is 30. What are the possible numbers?

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Question 158851: The sum of an interger and its square is 30. What are the possible numbers?
Found 2 solutions by nabla, edjones:
Answer by nabla(475) About Me  (Show Source):
You can put this solution on YOUR website!
a+a^2=30
a^2+a-30=0
(a-5)(a+6)=0
so a=5 or a=-6
a must be an integer therefore a=-6 is excluded.
a=5 is the only possible number.


Check:
5+25=30.
yes

Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
Let x= the integer.
x+x^2=30
x^2+x-30=0
(x+6)(x-5)=0
x=-6, x=5
.
Ed