An irregular pentagon with five different measured angles and five unequal sides. The angles of the pentagon are x degrees, 121 degrees, 108 degrees, 102 degrees, and 100 degrees.

it would be 6xy and -16xy.

the mistake in the pattern is that :

b. the decimal point was moved one too many place values each time

the correct pattern could be made by :

b. moving the decimal point to the right the same numbers of place values as the exponents