To add and subtract polynomials, combine only like terms. When doing it vertically, stack polynomials and line up the same bases and exponents. Once this is done, simply add and subtract the coefficients.
10x^2 + 12xy + 4x
+ 12x^2 -22xy + 8x
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22x^2 -10xy + 12x
Here we added 10 + 12 = 22, 12 + -22 = -10 and 4 + 8 = 12.
The sum of any integer and its opposite is equal to zero. adding two negative integers always yields a negative sum. To find the sum of a positive and a negative integer, take the absolute value of each integer and then subtract these values.
, we require
