SOLUTION: how do you find the sum of (-x^2+x+2)+(3x^2+4x+5)

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Question 73851: how do you find the sum of (-x^2+x+2)+(3x^2+4x+5)
Found 2 solutions by stanbon, Edwin McCravy:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
find the sum of (-x^2+x+2)+(3x^2+4x+5)
Add "like" terms to get:
2x^2+5x+7
Cheers,
Stan H.

Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
 
How do you find the sum of

(-x² + x + 2) + (3x² + 4x + 5)

Two ways, vertically and horizontally:

Vertically:
Place them so that like terms are lined up vertically:

   -x² +  x + 2
 + 3x² + 4x + 5
   2x² + 5x + 7

Horizontally:

(-x² + x + 2) + (3x² + 4x + 5)

Place 1's just before the parentheses

1(-x² + x + 2) + 1(3x² + 4x + 5)

and distribute to remove the parentheses:

-x² + x + 2 + 3x² + 4x + 5

Look for like terms:

-x² + x + 2 + 3x² + 4x  + 5

I have paired like terms by color.
 
The two red terms combine as 2x², the two blue 
terms combine as + 5x, and the two green terms 
combine as + 7. 

Answer: 2x²  + 5x + 7

or all in black:

        2x² + 5x + 7

Edwin