SOLUTION: Please explain to me exactly how to add and subtract polynomials. Ex: x^2+5;3x^2+9 or 7x^3-4x;3x^3 because I do not understand it. If there is a formula, please include the steps f

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Question 595645: Please explain to me exactly how to add and subtract polynomials. Ex: x^2+5;3x^2+9 or 7x^3-4x;3x^3 because I do not understand it. If there is a formula, please include the steps for it.
Answer by sdjackson71(2) (Show Source):
You can put this solution on YOUR website!
When adding and subtracting polynomials you only add those that share the same exponent. If the exponents do not match you cannot add them together. In your examples you give 2 problems. It helps me to set them up as so:
x^2 + 5
+ 3x^2 + 9 (lining up the matching exponent)
___________
4x^2 + 14 (add the numbers not the exponents, x^2 is essentially 1x^2)
Your second example:

7x^3 - 4x
+ 3x^3 (since there is nothing under the 4x you will just bring it down)
________________
10x^3 - 4x
I hope this helps. Always remember to look at the top problem and the bottom problem for the +/- signs if there had been a number in your second example it would have been added to -4x.
Good luck.