Respuesta :
the common difference is -10....that just means u have to add -10 to each number to find the next number
9 - 10 = -1
-1 - 10 = - 11
-11 - 10 = -21
etc...
** basically, common difference means u add and common ratio means u multiply
9 - 10 = -1
-1 - 10 = - 11
-11 - 10 = -21
etc...
** basically, common difference means u add and common ratio means u multiply