Complete each of the following questions by choosing the appropriate option from the choices provided.
a) If an equation has the same number of x's on each side, but different numbers, such as 8-6= 8z -2, then there is
b) If an equation has a different number of x's on each side, such as 7 - 5 = 9+2, then there is
c) If an equation has the same number of x's on each side, and the same numbers, such as 9x + 1 = 9z+1, then there is