SOLUTION: The sum of a number and its square is 56. Find the number. I believe its 7+49=56 but I don't know how to write it out. I must set up an Algebraic equation in order to get credit

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: The sum of a number and its square is 56. Find the number. I believe its 7+49=56 but I don't know how to write it out. I must set up an Algebraic equation in order to get credit      Log On


   

Question 249098: The sum of a number and its square is 56. Find the number. I believe its 7+49=56 but I don't know how to write it out. I must set up an Algebraic equation in order to get credit.
I appreciate your help!
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
The sum of a number and its square is 56. Find the number. I believe its 7+49=56 but I don't know how to write it out. I must set up an Algebraic equation in order to get credit.
I appreciate your help! 

x+%2B+x%5E2+=+56

x%5E2+%2B+x+-+56+=+0

%28x%2B8%29%28x-7%29%2B0

x+8 = 0;    x-7 = 0
  x = -8      x = 7

So there are two solutions, not just the one you thought of.

(-8)^2 + (-8) = 64 - 8 = 56

as well as yours:

   (7)^2 + (7) = 49 + 7 = 56

Edwin