Help please? :’)

Which values for a and b will create infinitely many solutions for this system of equations? ax-y=8 2x+y=b

Determine the quotient and remainder when (6a3)+11a2-4a-9) is divided by (3a-2) express your answer in the form q(a) + r(a)/d(a)

After the seventh month of a 12-month loan: the numerator is: {(n + 11) + (n + 10) + (n + 9) + (n + 8) + (n + 7) + (n + 6) + (n + 5)} = , and the denominator is: {(n) + (n + 1) + + (n + 11)} = . therefore, the fraction is numerator/denominator (to the nearest tenth) = %