Adding and Subtracting Exponents

You can add and subtract exponential expressions if they have the same
base and the same exponent. Just add or subtract the coefficients.

 
                  2      2       2
Example: 2x + 7x = 9 x . Only add the coefficient not the exponents .
                  2       3
Example: 2y - 10y If the exponents are different, the coefficients can not
be added or subtracted.
                  2       2
Example: 2x - 10y If the base (variable) is different the coefficients
can not be added.